Artisans and dugout canoes reveal pieces of Atlantic Forest history

Dugout canoes are boats made from a single tree trunk. Even with the modernization of fishing, they are still made and used for artisanal fishing on the coast of southern and southeastern Brazil and in other regions of the world. Various tree species are used to construct these canoes and choosing a species is related to characteristics of the location, available raw materials and purpose of the boat. Our objective was to better understand the variation in dugout canoes in relation to tree species, tree size and fishing use, over time, along a coastal strip of southern and southeastern Brazil within the Atlantic Forest domain. We interviewed 53 artisans and analyzed 358 canoes that ranged from 1 to around 200 years old. Schizolobium parahyba is currently used the most. In the past, species of the family Lauraceae (Nectandra sp. / Ocotea sp.) were frequently used, as well as Cedrela fissilis and Ficus sp. The size of the canoes varied based on time, coastal region, environment where the boat is used (exposed or sheltered) and type of fishing. The average size of recent canoes was smaller than older canoes for more common species (S. parahyba and C. fissilis), reflecting changes in the vegetation of the biome over time, both in the species and size of individuals available. Latitudinal variation can also influence the availability of tree species along the studied regions. An increase in environmental monitoring has contributed to a decline in constructing dugout canoes, resulting in the use of fiberglass canoes and other motorized boats. Although canoe size varied based on region, location and use, today some of the older canoes represent large trees of the past and pieces of Atlantic Forest history.独木舟（dugout canoe）是由单根树干凿制而成的船舶。即便渔业已实现现代化，这类船只在巴西南部、东南部沿海及全球其他地区仍被用于手工渔业作业。制作独木舟可选用多种树种，树种的选择与当地立地特征、可获取的原材料及船只用途紧密相关。本研究旨在深入探究巴西南部至东南部沿海大西洋森林生态域范围内，独木舟的形制变化与所用树种、树木尺寸及渔业用途之间的关联，且覆盖了较长的时间跨度。 研究团队共访谈了53位造船工匠，并对358艘船龄介于1年至约200年的独木舟开展了分析。目前应用最为广泛的造船树种为巴西蜜茱萸（*Schizolobium parahyba*）；过往则常采用樟科（Lauraceae）物种（润楠属*Nectandra* sp.、奥寇梯木属*Ocotea* sp.），以及红椿（*Cedrela fissilis*）和榕属*Ficus* sp.。 独木舟的尺寸会随时间、沿海区域、作业环境（暴露型或遮蔽型）以及渔业类型的不同而发生变化。针对较为常用的树种（如*S. parahyba*和*C. fissilis*），近年建造的独木舟平均尺寸小于老旧独木舟，这反映出该生物群区的植被随时间发生了演变，包括可获取林木的物种组成与个体尺寸。纬度梯度差异同样会影响研究区域内可获取造船树种的分布情况。 环境监管力度的不断加大导致独木舟建造量持续缩减，玻璃钢（fiberglass）独木舟及其他机动船只的使用比例逐步上升。尽管独木舟尺寸会因区域、作业地点与用途的不同而存在差异，但如今部分老旧独木舟仍承载着过往大型林木的历史印记，同时也是大西洋森林历史的实物见证。