scholarly journals Comparison of Forwarder Productivity and Optimal Road Density in Thinning and Clearcutting of Pine Plantation in Southern Brazil

2021 ◽  
Vol 43 (1) ◽  
Author(s):  
Daiane Alves de Vargas ◽  
Franciny Lieny Souza ◽  
Jean Alberto Sampietro ◽  
Marcos Felipe Nicoletti ◽  
Marcelo Bonazza ◽  
...  
Keyword(s):  
Forest Management ◽  
Road Density ◽  
Geometry Model ◽  
Management Regime ◽  
Time And Motion ◽  
Wood Extraction ◽  
The Difference ◽  
Process Factors ◽  
Motion Studies ◽  
Pinus Taeda L

The prescription of forest management determines the number of trees to be cut and, consequently, the harvested wood volume, which directly influences the forest operations dynamic. The objectives of this paper were (i) to analyze the effect of process factors on wood extraction performance with forwarder in first thinning and clearcutting of Pinus taeda L. plantations; and (ii) to economically determine the optimal road density to manage these plantations. Time and motion studies at the cycle element level were conducted to quantify and model the time consumption, productivity, and operational costs of the extraction. The optimal road density (ORD) for both operation types (OT) was determined based on the transport geometry model, considering the minimization of the sum of unitary costs with construction and maintenance of roads, loss of productive area, and wood extraction. The extraction distance (ED), slope (SL), average log volume (LV), and OT had a significant effect on the time consumed in travels, and therefore, on productivity (PPMH). In clearcutting, the average PPMH was 12.17 m3ob PMH0-1, while, in thinning, it was 10.94 m3ob PMH0-1; however, as the ED increased, the difference of PPMH and the cost of extraction between the operations decreased, which highlighted a greater effect of this factor on forwarder’s work in clearcutting. For this reason, the ORD for clearcutting (37.76 m ha-1) was higher than for thinning (27.84 m ha-1). Therefore, we demonstrated in this study that the type of operation and forest management regime, as well as their interaction with process factors, affect the sizing of the number of roads per unit area, and also the costs of the forest activity.

scholarly journals INFLUENCE OF WHEELED TYPES OF A Skidder ON PRODUCTIVITY AND COST OF THE FOREST HARVESTING

FLORESTA ◽  
2013 ◽  
Vol 44 (1) ◽  
pp. 53 ◽  
Author(s):  
Eduardo Silva Lopes ◽  
Diego De Oliveira ◽  
Jean Alberto Sampietro
Keyword(s):  
Pinus Taeda ◽  
Forest Harvesting ◽  
Operating Efficiency ◽  
Time And Motion Study ◽  
Time And Motion ◽  
Operational Costs ◽  
Wood Extraction ◽  
Motion Study ◽  
Pinus Taeda L ◽  
Lower Production

AbstractThe objective of this study was to evaluate the influence of different wheel types of a skidder on productivity and cost of Pinus taeda L. wood extraction. The study was conducted in a forestry company located in the municipality of Mandirituba, Paraná state, Brazil. The technical and cost analyses included a time and motion study of the wood extraction activity. The productivity, operative efficiency, energy consumption and the production and operational costs were determined for the machines with different wheel types: SDP - skidder with rubber tires; SD2 – skidder with tracks on the two front tires; and SD4 – skidder with tracks on the four tires. Results showed that the activity that demanded most time in the operational cycle was the maneuvering of the machines to pick up more than one tree, resulting in lost of productivity and need of improvement in the operational planning. The skidder equipped only with rubber tires showed higher productivity and lower production cost in the longest extraction distances, caused by the higher operating speed of the machine.Keywords: Timber extraction; wheel types; operating efficiency. ResumoInfluência dos rodados de um skidder na produtividade e no custo da extração florestal. Este trabalho objetivou avaliar a influência de diferentes tipos de rodados de um skidder na produtividade e no custo da extração de madeira de Pinus taeda L. O estudo foi conduzido em uma empresa florestal localizada no município de Mandirituba, estado do Paraná, Brasil. As análises técnica e de custo englobaram um estudo de tempos e movimentos da operação de extração florestal. Foi determinado a produtividade, eficiência operacional, rendimento energético e custos operacionais e de produção das máquinas equipadas com diferentes tipos de rodados: SDP – skidder com rodados de pneus; SD2 – skidder com pneus dianteiros recobertos com semiesteiras e SD4 – skidder com os quatro pneus recobertos com semiesteiras. Os resultados mostraram que a atividade que demandou o maior tempo do ciclo operacional foram as manobras realizadas pelas máquinas para apanhar mais de uma árvore, ocasionando perda de produtividade e necessidade de melhoria no planejamento operacional. O skidder equipado somente com rodados de pneus apresentou maior produtividade e menor custo de produção nas maiores distâncias de extração, ocasionado pela maior velocidade operacional da máquina.Palavras-chave: Extração florestal; tipos de rodados; eficiência operacional.

scholarly journals Soil Moisture Dynamics in Response to Precipitation and Thinning in a Semi-Dry Forest in Northern Mexico

Water ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 105
Author(s):  
Argelia E. Rascón-Ramos ◽  
Martín Martínez-Salvador ◽  
Gabriel Sosa-Pérez ◽  
Federico Villarreal-Guerrero ◽  
Alfredo Pinedo-Alvarez ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Forest Management ◽  
Water Availability ◽  
Dry Forest ◽  
Rainfall Events ◽  
Rainfall Characteristics ◽  
Northern Mexico ◽  
The Difference ◽  
The Impact ◽  
Moisture Dynamics

Understanding soil moisture behavior in semi-dry forests is essential for evaluating the impact of forest management on water availability. The objective of the study was to analyze soil moisture based in storm observations in three micro-catchments (0.19, 0.20, and 0.27 ha) with similar tree densities, and subject to different thinning intensities in a semi-dry forest in Chihuahua, Mexico. Vegetation, soil characteristics, precipitation, and volumetric water content were measured before thinning (2018), and after 0%, 40%, and 80% thinning for each micro-catchment (2019). Soil moisture was low and relatively similar among the three micro-catchments in 2018 (mean = 8.5%), and only large rainfall events (>30 mm) increased soil moisture significantly (29–52%). After thinning, soil moisture was higher and significantly different among the micro-catchments only during small rainfall events (<10 mm), while a difference was not noted during large events. The difference before–after during small rainfall events was not significant for the control (0% thinning); whereas 40% and 80% thinning increased soil moisture significantly by 40% and 53%, respectively. Knowledge of the response of soil moisture as a result of thinning and rainfall characteristics has important implications, especially for evaluating the impact of forest management on water availability.

scholarly journals Aboveground stock of biomass and organic carbon in stands of Pinus taeda L.

CERNE ◽  
2013 ◽  
Vol 19 (3) ◽  
pp. 509-515 ◽  
Author(s):  
Luciano Farinha Watzlawick ◽  
Marcos Vinicius Winckler Caldeira ◽  
Tiago de Oliveira Godinho ◽  
Rafaelo Balbinot ◽  
Jonathan William Trautenmüller
Keyword(s):  
Forest Management ◽  
Organic Carbon ◽  
Pinus Taeda ◽  
Management Practices ◽  
Tree Density ◽  
Stem Wood ◽  
Quantification Method ◽  
Forest Management Practices ◽  
Pinus Taeda L ◽  
Age Category

This study aimed to estimate biomass and organic carbon in stands of Pinus taeda L. at different ages (14, 16, 19, 21, 22, 23 and 32 years) and located in the municipality of General Carneiro (PR). In order to estimate biomass and organic carbon in different tree components (needles, live branches, dead branches, bark and stem wood), the destructive quantification method was used in which seven trees from each age category were randomly sampled across the stand. Stocks of biomass and organic carbon were found to vary between the different age categories, mainly as a result of existing dissimilarities between ages in association with forest management practices such as thinning, pruning and tree density per hectare.

scholarly journals The Costs of Home-Based ART Initiation and Mobile Refill in Uganda

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S436-S436
Author(s):  
D Allen Roberts ◽  
Stephen Asiimwe ◽  
Bosco Turyamureeba ◽  
Ruanne Barnabas
Keyword(s):  
Large Scale ◽  
Viral Suppression ◽  
Geographic Area ◽  
Outreach Worker ◽  
Eligibility Criteria ◽  
Time And Motion Studies ◽  
Art Initiation ◽  
Time And Motion ◽  
Home Based ◽  
Motion Studies

Abstract Background Antiretroviral therapy (ART) is effective at reducing HIV-associated morbidity, mortality, and transmission, but 20 million people who meet WHO eligibility criteria for ART are not in care. While decentralized care is a promising strategy to expand ART access, the costs of implementing a community-based model on a large scale remain unknown. Methods The DO-ART study is a randomized trial of community- vs. clinic-centered ART delivery in South Africa and Uganda using 12-month viral suppression as the primary outcome. We evaluated the costs of home-based ART initiation and refill in southwest Uganda using time-and-motion studies, staff interviews, and budgetary analysis. Costs categories included medications, supplies, personnel, building and utilities, start-up, vehicles, and community mobilization. We used a programmatic perspective with a 3% discount rate and removed research-associated costs. Results The largest cost categories included medications, supplies, and salaries, constituting 41%, 27%, and 17% of the total cost, respectively. Time-and-motion studies revealed that each outreach worker could serve an average of three patients per day in a fully decentralized model. In a scenario of providing home-based ART to 1400 patients aross seven sub-counties, the yearly per-patient cost was estimated to be $304 (2016 USD), which is similar to literature reports of the costs of facility-based ART provision. Conclusion These estimates suggest that home-based ART may be a realistic delivery option, especially if it is found to be effective at improving viral suppression. Further research is needed to evaluate how this intervention can most efficiently scale to provide widespread ART access over a large geographic area. Disclosures All authors: No reported disclosures.

scholarly journals PERANAN KETELADANAN ORANG TUA DALAM MEMBENTUK KEPRIBADIAN DAN AKHLAK ANAK DI SDN CIBULUH 02 BOGOR UTARA

2018 ◽  
Vol 1 (1) ◽  
pp. 31-104
Author(s):  
Amalliah Kadir
Keyword(s):  
Qualitative Research ◽  
Time Management ◽  
Role Model ◽  
Sampling Method ◽  
Good Time ◽  
Time And Motion ◽  
Role Of Parents ◽  
Motion Studies ◽  
Good Behaviour

This research was conducted to examine more deeply the role ofparents in shaping personality, morals and any factors that becomeobstacles and supporters in shaping children's personality and moralsin SDN 02 Cibuluh Bogor Utara. It is a qualitative research with datacollection methods (observation, interview, documentation), thenanalyzed using descriptive methods (by recording and reviewing allresults of data obtained from various sources, case studies, comparativestudies, time and motion studies, behavior analysis) and the object ofthis research was chosen by purposive sampling method. The results ofthis study get clarity that the importance of the role of parents inshaping personality, including: good time management, smile,greetings, and familiarize good behaviour. The role of parents inshaping morality includes: always remember to die, fear of Allah,always reminding that everything we have can not be taken into theafterlife-world except our valuable knowledge that we had done in life,shadaqah jariyah, and the prayer of the good children. The importantrole of parents is as the child companion, as a preacher and qudwahhasanah (good role model), controller, motivator, mediator, technicalmanager of children in every process of child development, especiallyin aspects of personality and morals.  

scholarly journals Influence of bifurcation on thinning, productivity and harvester production costs of Pinus taeda L.

2020 ◽  
pp. 1259-1263
Author(s):  
Carlos Cézar Cavassin Diniz ◽  
Romano Timofeiczyk Junior ◽  
Renato Gonçalves Robert ◽  
Eduardo da Silva Lopes ◽  
João Carlos Garzel Leodoro da Silva ◽  
...  
Keyword(s):  
Pinus Taeda ◽  
Cycle Time ◽  
Production Costs ◽  
Total Production ◽  
Plantation Forest ◽  
Operating Cycle ◽  
Operational Cycle ◽  
Time And Motion ◽  
Motion Study ◽  
Pinus Taeda L

In this work, we present that how bifurcation in Pinus trees can influence productivity and harvester production costs. Our example draws from one harvesting machine that works in thinning operations in forest plantations of Pinus taeda L. in a small Brazilian forestry company. To get daily productivity, we use the machine’s system, which provides such daily information as total production. We also used a time and motion study to obtain the meantime to cut, delimb, and process the tree stem into logs. In this way, we separated the normal trees from the forked trees to get the operating cycle time of the machine and get the productivity to the two types of trees. The continuous timing method was used for this purpose. The results show an increase of up to 22.9% in the operational cycle time for cutting forked trees, resulting in reduction of productivity of 5.58 m³ for each hour worked. The production cost increased by 23.3% on operation of forked trees, as the machine took more time to perform the partial activities of the operational cycle. This study can help many companies and contractors to calculate the appropriate productivity and production harvest cost according to the type of tree stems from the plantation forest.

scholarly journals Summertime canopy albedo is sensitive to forest thinning

2013 ◽  
Vol 10 (9) ◽  
pp. 15373-15414 ◽  
Author(s):  
J. Otto ◽  
D. Berveiller ◽  
F.-M. Bréon ◽  
N. Delpierre ◽  
G. Geppert ◽  
...  
Keyword(s):  
Forest Management ◽  
Tree Species ◽  
Structural Changes ◽  
Near Infrared ◽  
Canopy Structure ◽  
Model Parameters ◽  
Transfer Model ◽  
Forest Thinning ◽  
Crown Volume ◽  
The Difference

Abstract. Despite an emerging body of literature linking canopy albedo to forest management, understanding of the process is still fragmented. We combined a stand-level forest gap model with a canopy radiation transfer model and satellite-derived model parameters to quantify the effects of forest thinning, that is removing trees at a certain time during the forest rotation, on summertime canopy albedo. The effects of different forest species (pine, beech, oak) and four thinning strategies (light to intense thinning regimes) were examined. During stand establishment, summertime canopy albedo is driven by tree species. In the later stages of stand development, the effect of tree species on summertime canopy albedo decreases in favour of an increasing influence of forest thinning on summertime canopy albedo. These trends continue until the end of the rotation where thinning explains up to 50% of the variance in near-infrared canopy albedo and up to 70% of the variance in visible canopy albedo. More intense thinning lowers the summertime shortwave albedo in the canopy by as much as 0.02 compared to unthinned forest. The structural changes associated with forest thinning can be described by the change in LAI in combination with crown volume. However, forests with identical canopy structure can have different summertime albedo values due to their location: the further north a forest is situated, the more the solar zenith angle increases and thus the higher is the summertime canopy albedo, independent of the wavelength. Despite the increase of absolute summertime canopy albedo values with latitude, the difference in canopy albedo between managed and unmanaged forest decreases with increasing latitude. Forest management thus strongly altered summertime forest albedo.

scholarly journals The Financially Optimal Loblolly Pine Planting Density and Management Regime for Nonindustrial Private Forestland in East Texas

2005 ◽  
Vol 29 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Ching-Hsun Huang ◽  
Gary D. Kronrad ◽  
Jason D. Morton
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Optimal Number ◽  
Planting Density ◽  
East Texas ◽  
Rates Of Return ◽  
Management Regime ◽  
Pinus Taeda L ◽  
Economic Analyses ◽  
Private Forestland

Abstract Economic analyses were conducted to investigate the effects of initial planting density on the profitability of loblolly pine (Pinus taeda L.) on nonindustrial private forestland (NIPF) in East Texas. Five planting densities of 870, 725, 620, 540, and 484 trees per acre (tpa)representing spacings of 5×10, 6×10, 7×10, 8×10, and 9×10 ft, respectively, were investigated. Land expectation values were used to determine the financially optimal thinning and final harvesting schedules (including rotation length and the timing, frequency, and intensity of thinning). Five site indices (50–90), six real alternative rates of return (ARR) (2.5–15.0%), and three thinning options (0, 1, and 2) were employed. Results indicate that two thinnings appear to be the financially optimal number of thinnings for most siteindex-ARR scenarios. The planting spacing of 8×10 ft is optimal when ARR is low, and the 9×10 ft spacing is optimal when ARR is high. South. J. Appl. For. South. J. Appl. For. 29(1):16–21.

scholarly journals The Profitability of Cross-Cutting Practices in Butt-Rotten Picea abies Final-Felling Stands

Forests ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 874 ◽  
Author(s):  
Kärhä ◽  
Räsänen ◽  
Palander
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Processing Time ◽  
Wood Quality ◽  
Study Data ◽  
Heterobasidion Annosum ◽  
Time And Motion ◽  
The Cross ◽  
Motion Studies ◽  
The Impact

Research Highlights: This study offers new information on the cross cutting of decayed stems with the sounding of short (0.5 m) offcuts and the bucking of longer (3.0 m) butt-rotten poles. Background and Objectives: The root and butt-rot fungus Heterobasidion annosum sensu lato (Fr.) Bref. causes wood quality damage to trees in softwood forests. When timber is harvested in butt-rotten forests, it is essential that the decayed part of the tree is recognized and cut away from a stem, while the healthy and good quality log section of a stem is cross cut with precision sawlogs. The objective of the study was to investigate the impact of two off-cutting methods on stem processing time, cutting productivity, sawlog volume, and commercial value at the roadside landing when harvesting timber from the butt-rotten Norway spruce (Picea abies (L.) Karst.) final-felling forests. Materials and Methods: The length of the short offcuts used was 0.5 m. The results of the cross-cutting practices were compared to the decayed pulpwood poles of 3 m from the butt of the rotten stems. Time and motion studies were carried out in stands before the profitability calculations. The study data consisted of 1980 Norway spruce sawlog stems. Results: Sounding of the short offcuts added significantly to the stem processing time of butt-rotten stems, but the sawlog volume and the timber value recovery of the stems were higher than those of the decayed pulpwood poles of 3 m. Conclusions: The study concluded that sounding of butt-rotten Norway spruce stems with one to three offcuts is economically profitable if the diameter of the decayed column at the stem stump’s height is small (≤5 cm). In contrast, when the width of the decay is larger (>5 cm), it is more profitable to first cross cut the decayed pulpwood pole of 3 m and then to observe the height of the decayed part of the stem.

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