Key Message Tree-level forest inventory data are becoming increasingly available, which motivates the use of these data for decision-making. However, airborne inventories carried out tree-by-tree typically include systematic errors, which can propagate to objective function variables used to determine optimal forest management. Effects of under-detection focused on the smallest trees on predicted immediate harvest profits and future expectation values were assessed assuming different sites and interest rates. Management decisions based on the erroneous information caused losses of 0–17% of the total immediate and future expected income of Scots pine stands. Context Optimal decisions on how to manage forest stands can depend on the absence or presence of intermediate and understory trees. Yet, these tree strata are likely prone to inventory errors. Aims The aim of this study is to examine implications of making stand management decisions based on data that include systematic errors resembling those typically observed in airborne inventories carried out tree-by-tree. Methods Stand management instructions were developed based on theoretical diameter distribution functions simulated to have different shape, scale, and frequency parameters corresponding to various degrees of under-detection focused on the smallest trees. Immediate harvest income and future expectation value were derived based on various management alternatives simulated. Results Errors in diameter distributions affected the predicted harvest profits and future expectation values differently between the simulated alternatives and depending on site type and interest rate assumptions. As a result, different alternatives were considered as optimal management compared to the use of the error-free reference distributions. In particular, the use of no management or most intensive management alternatives became preferred over alternatives with intermediate harvesting intensities. Certain harvesting types such as thinning from below became preferred more often than what was optimal. The errors did not affect the selection of the management alternative in 71% of the simulations, whereas in the remaining proportion, relying on the erroneous information would have caused losing 2%, on average, and 17% at maximum, of the total immediate and future expected income. Conclusion The effects above might not have been discovered, if the results were validated for inventory totals instead of separately considering the immediate and future income and losses produced by the erroneous decisions. It is recommended not to separate but to integrate the inventory and planning systems for well-informed decisions.

中文翻译：

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根据模拟的个体树木检测，直径分布误差对林分管理决策的影响

关键信息 树级森林清单数据变得越来越可用，这促使人们使用这些数据进行决策。然而，逐树进行的空中清单通常包括系统误差，这些误差可以传播到用于确定最佳森林管理的目标函数变量。假设不同的地点和利率，评估了针对最小树木的检测不足对预测的即时收获利润和未来期望值的影响。基于错误信息的管理决策造成了 0-17% 的苏格兰松林近期和未来预期总收入的损失。背景 关于如何管理林分的最佳决策取决于中间和林下树木的存在与否。然而，这些树层很可能容易出现库存错误。目的 本研究的目的是检查基于数据做出林分管理决策的影响，这些数据包括系统错误，类似于在逐棵树进行的空中盘查中通常观察到的系统错误。方法基于理论直径分布函数制定林分管理指令，模拟具有不同形状、规模和频率参数，对应于针对最小树木的不同程度的检测不足。即时收获收入和未来预期值是根据模拟的各种管理方案得出的。结果 直径分布的误差对模拟备选方案之间的预测收获利润和未来预期值的影响不同，取决于场地类型和利率假设。因此，与使用无错误参考分布相比，不同的替代方案被认为是最佳管理。特别是，使用无管理或最集约化管理替代方案比具有中等收获强度的替代方案更受欢迎。某些收割类型（例如从下方变薄）比最佳采收方式更受欢迎。在 71% 的模拟中，错误没有影响管理替代方案的选择，而在剩余的比例中，依赖错误信息会导致平均损失 2%，最多损失 17%未来的预期收入。结论 上面的效果可能没有被发现，如果结果对存货总额进行了验证，而不是单独考虑由错误决策产生的近期和未来收入和损失。建议不要将清单和计划系统分开，而是将其集成在一起，以便做出明智的决策。