Prior to the 1950s, common partial harvesting operations in the southern Appalachians USA involved the removal of logs by ground-skidding and the construction of steep access roads and skid trails along stream channels. Little is known about how these historical practices affected long-term vegetation changes. An experimental watershed in the Coweeta Hydrologic Laboratory was partially harvested in the years 1942–1952 according to these exploitive practices. We compared the partial-cut watershed to a clear-cut watershed and an untreated, reference watershed. Using long-term vegetation surveys, we analyzed patterns in aboveground biomass accumulation, species composition and diversity (Shannon’s index Hʹ and species richness) among watersheds. Contrary to our expectations, the partial-cut watershed recovered to reference levels of aboveground biomass and their species composition was similar over time. The clear-cut watershed had greater abundance of tulip poplar (Liriodendron tulipifera) and black locust (Robinia pseudoacacia) than the other two watersheds. The partial-cut watershed increased in diversity over time, but it remained less diverse than the reference watershed; whereas, the clear-cut watershed had lower diversity than the other two watersheds, and its diversity did not change over time. Distributions of functional groups based on water use and nutrient acquisition traits, and shade tolerance were similar between the partial-cut and the reference watersheds, but differed from the clear-cut watershed. By the 2010s, partial-cut and reference watersheds had similar proportions of diffuse-porous (32% and 33%) and ring-porous (48% and 42%) basal area, while the clear-cut watershed had more diffuse-porous (43%) and less ring-porous (36%) species than the partial-cut or reference watersheds. Tree species associated with arbuscular mycorrhiza were more abundant in the clear-cut watershed than the partial-cut or reference watersheds. Overall, the partial-cut watershed, even with the extreme soil disturbance, did not alter long-term species composition and diversity as dramatically as the clear-cut watershed. These results could help forest managers, conservationists, and hydrologists understand the long-term effects of partial-cutting versus clear-cutting.

中文翻译：

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美国南部阿巴拉契亚山脉长期砍伐而不是砍伐的案例

在1950年代之前，美国南部的阿巴拉契亚人普遍进行部分收割作业，涉及通过打滑清除原木，以及修建沿河道的陡峭通道和滑道。对于这些历史习俗如何影响长期植被变化知之甚少。根据这些开发实践，在1942年至1952年间，科韦塔水文实验室的一个实验分水岭被部分收获。我们将部分切割的分水岭与一个清晰的分水岭和一个未经处理的参考分水岭进行了比较。通过长期的植被调查，我们分析了流域之间地上生物量积累，物种组成和多样性（香农指数Hʹ和物种丰富度）的模式。与我们的期望相反，随着时间的流逝，部分切割流域恢复到地上生物量的参考水平，并且其物种组成相似。明确的分水岭拥有更多的郁金香杨树（鹅掌tu和刺槐（刺槐））比其他两个分水岭。随着时间的流逝，部分砍伐的分​​水岭的多样性有所增加，但与参考分水岭相比，多样性仍然较低。明确的分水岭的多样性低于其他两个分水岭，并且其多样性不会随时间变化。在部分流域和参考流域之间，基于水分利用和养分获取特征以及耐荫性的功能组分布相似，但与明晰流域不同。到2010年代，部分切割流域和参考流域的散布孔基础面积比例分别为32％和33％和环孔（48％和42％），而清晰分水岭的散布孔比例更高（比部分切割流域或参考流域少43％）和少环孔（36％）物种。与丛枝菌根相关的树木种类在部分集水区比参考分水岭更为丰富。总体而言，即使受到极端土壤干扰，部分切割的分水岭也没有像清除型分水岭那样显着改变长期物种组成和多样性。这些结果可以帮助森林管理者，保护主义者和水文学家了解部分砍伐与明确砍伐的长期影响。