Botha M Susan, Cowling Richard M, De Vynck Jan C, Esler Karen J, Potts Alastair J
Botany Department, African Centre for Coastal Palaeoscience, Gqeberha, Eastern Cape, South Africa.
Stellenbosch University, Conservation Ecology & Entomology, Stellenbosch, Western Cape, South Africa.
PeerJ. 2022 May 3;10:e13066. doi: 10.7717/peerj.13066. eCollection 2022.
Current ecological understanding of plants with underground storage organs (USOs) suggests they have, in general, low rates of recruitment and thus as a resource it should be rapidly exhausted, which likely had implications for hunter-gatherer mobility patterns. We focus on the resilience (defined here as the ability of species to persist after being harvested) of USOs to human foraging. Human foragers harvested all visible USO material from 19 plots spread across six Cape south coast (South Africa) vegetation types for three consecutive years (2015-2017) during the period of peak USO apparency (September-October). We expected the plots to be depleted after the first year of harvesting since the entire storage organ of the USO is removed during foraging, . immediate and substantial declines from the first to the second harvest. However, over 50% of the total weight harvested in 2015 was harvested in 2016 and 2017; only after two consecutive years of harvesting, was there evidence of significantly lower yield ( = 0.034) than the first (2015) harvest. Novel emergence of new species and new individuals in year two and three buffered the decline of harvested USOs. We use our findings to make predictions on hunter-gatherer mobility patterns in this region compared to the Hadza in East Africa and the Alyawara in North Australia.
当前对具有地下贮藏器官（USOs）植物的生态学认识表明，总体而言，它们的更新率较低，因此作为一种资源，应该会迅速枯竭，这可能对狩猎采集者的流动模式产生影响。我们关注地下贮藏器官对人类觅食的恢复力（这里定义为物种在被收获后持续存在的能力）。在地下贮藏器官最明显的时期（9月至10月），人类觅食者连续三年（2015 - 2017年）从分布在南非开普敦南海岸六种植被类型的19个地块中收获了所有可见的地下贮藏器官物质。由于在觅食过程中地下贮藏器官的整个贮藏部分都被移除，我们预计在收获的第一年之后这些地块就会枯竭，即从第一次收获到第二次收获会立即出现大幅下降。然而,2016年和2017年收获的总量超过了2015年收获总量的50%；只有在连续两年收获之后，才有证据表明产量（= 0.034）明显低于第一次（2015年）收获。第二年和第三年新物种和新个体的出现缓冲了收获的地下贮藏器官的下降。我们利用研究结果对该地区狩猎采集者的流动模式与东非的哈扎人和北澳大利亚的阿利亚瓦拉人进行了比较预测。
