Charcoal is an important urban fuel; however, when production is unregulated, it is a major cause of land and forest degradation. Production through selective harvesting of the preferred large, hardwood tree species leads to a degraded residual forest or woodland composed of juvenile hardwood trees and unused softwood tree species. This situation can be addressed by ensuring that the rate of preferred tree species extraction does not exceed the mean annual increment. This study estimated the sustainable rate of tree harvesting for charcoal in Mutomo District, based on field data collected between December 2012 and January 2013, through a forest inventory. The woodlands are subjected to selective logging for charcoal production, an activity undertaken by about half of the residents for their livelihood. The study findings show that charcoal production through selective logging has led to a reduction of the hardwood trees biomass density to 3.8 t ha⁻¹ compared with an estimated desirable level of 12.5 t ha⁻¹. The results also show that it would take between 25 and 31 years for the woodlands to recover to the desirable stocking level if harvesting was completely stopped. This duration would increase to between 54 and 64 years if 80% of the mean annual increment was harvested for charcoal production and 20% was retained for woodlands recovery. As the residents of Mutomo District are poor and highly dependent on charcoal production for their livelihood, a harvesting plan based on the latter option would set the woodlands on the path to recovery and ensuring a sustainable livelihood source.

中文翻译：

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估计木炭生产的可持续生物量采伐水平，以促进退化的林地的恢复：来自肯尼亚穆托莫区的案例研究

木炭是重要的城市燃料。然而，当生产不受管制时，这是土地和森林退化的主要原因。通过选择性地采伐优选的大型硬木树种进行生产，会导致退化的残留森林或林地，其中包括少年硬木树和未使用的软木树种。可以通过确保首选树种的提取率不超过平均年增量来解决这种情况。这项研究基于2012年12月至2013年1月之间通过森林调查收集的实地数据，估算了Mutomo区木炭的可持续采伐率。对林地进行选择性伐木以生产木炭，约有一半的居民以生计为生。^-1与估计的12.5 t ha ^-1的理想水平相比。结果还表明，如果完全停止采伐，林地将需要25到31年才能恢复到理想的放养水平。如果将年均增量的80％用于木炭生产并将20％用于林地恢复，则这一持续时间将增加到54至64年之间。由于Mutomo区的居民很贫穷，并且高度依赖木炭生产来维持生计，因此基于后一种选择的采伐计划将使林地走上恢复之路，并确保可持续的生计来源。