ECONOMIC AND OPERATIONAL ANALYSIS OF MECHANIZED FOREST IMPLEMENTATION

ABSTRACT Mechanization in forestry implantation demands high energy, time, and high operational and production costs. Thus, studies related to the influence of variables on the efficiency of these activities are essential to reduce costs and optimize operations. The objective of this study was to evaluate the operational and cost performance of mechanized forest implantation operations in Eucalyptus sp. Data were collected from eucalyptus plantations located in the northern region of the state of Espírito Santo, Brazil. The analysis of operational performance determined the distribution of operating times, mechanical availability, degree of utilization, operational efficiency, and productivity of the machines. The cost analysis estimated the operating costs in forestry implantation activities. The forest planting operations were: waste removal, subsoiling, digging with fertilization, planting, chemical weeding, and covering fertilization. According to the results, planting (39.20%) and waste removal (15.99%) represented the longest operating cycle times, the shortest production times (51.48% and 53.64%), and finally the longest maintenance times (32.95% and 29%). Chemical weeding and subsoiling showed the lowest maintenance times (4.64% and 3.47%). The cover fertilization was the operation that presented the highest productivity (2.99 ha he-1), and the removal of residues had the lowest (0.97 ha he-1). The highest costs per effective hour (R$13.57 he-1) and lowest production costs (R$81.59 ha-1) occurred at planting. Subsoiling had the highest production cost (R$112.80 ha-1). The lowest operating cost was obtained in the fertilizing operation. Operating costs had the greatest weight in labor, fuel, and maintenance and repairs.

摘要
林业造林机械化作业能耗高、耗时久，且作业与生产成本高昂。因此，探究作业变量对该类活动效率的影响，对降低成本、优化作业流程至关重要。本研究旨在评估桉树属（Eucalyptus sp.）人工林机械化造林作业的作业与成本绩效。
研究数据采集自巴西圣埃斯皮里图州北部地区的桉树人工林。作业绩效分析涵盖了作业时间分布、机械可用率、设备利用率、作业效率以及机器生产率等维度；成本分析则对林业造林作业的运营成本进行了估算。本次研究涉及的造林作业工序包括：伐区清理、深松整地、施肥挖穴、苗木定植、化学除草以及覆土施肥。
研究结果显示，苗木定植（39.20%）与伐区清理（15.99%）的作业循环时长占比最高，其生产时长占比却最低（分别为51.48%与53.64%），而维修时长占比则最高（分别为32.95%与29%）。化学除草与深松整地的维修时长占比最低，分别为4.64%与3.47%。
覆土施肥作业的生产率最高，可达2.99公顷/小时，而伐区清理作业的生产率最低，仅为0.97公顷/小时。苗木定植作业的单有效小时成本最高，达13.57巴西雷亚尔（R$）/有效小时，单位公顷生产成本最低，为81.59巴西雷亚尔（R$）/公顷。深松整地作业的单位公顷生产成本最高，达112.80巴西雷亚尔（R$）/公顷。施肥作业的运营成本最低。运营成本构成中，人工、燃油以及维修保养占比最高。