Population Structure of Brazil Nut (Bertholletia excelsa, Lecythidaceae) Stands in Two Areas with Different Occupation Histories in the Brazilian Amazon
Population Structure of Brazil Nut (Bertholletia excelsa, Lecythidaceae) Stands in Two Areas with Different Occupation Histories in the Brazilian Amazon
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巴西坚果（Bertholletia excelsa，Lecythidaceae）的种群结构分布在巴西亚马逊地区两个不同占领历史的地区
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发表时间：
2011
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影响因子：
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通讯作者：
R. Gribel
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作者：
Ricardo Scoles;R. Gribel
在这里，我们假设巴西坚果林（castanhais）中人类活动引起的干扰强度与巴西坚果树（Bertholletia excelsa H.B.K.，因此，本种的种群结构较年轻。为了验证这一假设，我们比较了巴西亚马逊河流域两个地区的巴西坚果树的人口结构，这些地区的人类土地使用历史不同。考古学和历史数据表明，特龙贝塔斯河周围地区在前哥伦布时代人口稠密，在欧洲人与美洲印第安人接触后，特别是在16世纪世纪，人口减少。在该地区抽样的25个巴西坚果林中，老B占优势。excelsa树木和有稀缺的招聘在林下。这些非常成熟的林分可能起源于16 - 17世纪土著人民的人口减少和19世纪初前逃亡奴隶的建立之间的间隔。第二个研究区域位于马德拉河（卡帕纳格兰德湖）附近，那里的castanhais更容易接近且受到干扰。在该立地条件下，B种群结构年轻，更新旺盛.在10个样地中观察到Excelsa。该地区的历史数据表明，土著人口从世纪开始逐渐被取代，没有证据表明人口严重减少。我们认为，不同的历史和当代土地利用模式的castanhais在这两个地点目前形成鲜明对比的人口结构。这些数据还支持这样一种观点，即栗树，即使是被认为是原始和“原生”森林，也是人为影响的结果。我们没有发现任何证据支持限制种子收获作为一种手段，以提高巴西坚果林的再生率。
Here we hypothesize that the intensity of disturbances caused by human activities in Brazil nut stands (castanhais) is positively related with the regeneration of Brazil nut trees (Bertholletia excelsa H.B.K., Lecythidaceae) and consequently with a younger population structure of this species. In order to test this hypothesis we compared the population structure of Brazil nut trees in two areas of the Brazilian Amazon with different histories of land usage by humans. Archeological and historical data suggest that the region surrounding the Trombetas River was densely occupied in pre-Columbian times and experienced depopulation after European contact with Amerindian populations, especially in the 16th century. The 25 Brazil nut stands sampled in this region were dominated by old B. excelsa trees and had scarce recruitment in the understory. These very mature stands likely owe their origins to the interval between the depopulation of the indigenous peoples in the 16th-17th centuries and the establishment of quilombos at the beginning of the 19th century. The second study area was in the vicinity of the Madeira River (Capanã Grande Lake), where the castanhais were more accessible and disturbed. In this site, a younger population structure and abundant regeneration of B. excelsa were observed in the 10 sampled stands. Historical data from this region indicate that indigenous populations were replaced gradually beginning in the 18th century, with no evidence of severe depopulation. We suggest that the different historical and contemporary land use patterns contributed to the current contrasting population structures of the castanhais at the two locations. The data also support the idea that the castanhais, even the ones considered to be pristine and “native” forests, result from anthropogenic influences. We found no evidence to support restrictions on seed harvesting as a means to improve regeneration rates of Brazil nut stands.