Programa de Pós-Graduação em Ecologia e Conservação, Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, 79070-900, Brazil.
Grupo de Pesquisa em Ecologia Florestal, Instituto de Desenvolvimento Sustentável Mamirauá (IDSM), Tefé, Amazonas, Brazil.
Sci Rep. 2020 Feb 25;10(1):3424. doi: 10.1038/s41598-020-60402-x.
Climatic factors can influence the establishment and growth of wood species, but little is known about the effect of these factors on monodominant communities in wetlands. Therefore, we asked how climatic factors, such as ENSO (El Niño-Southern Oscillation), precipitation and flooding, influence growth and establishment of the dominant species Erythrina fusca in the Pantanal. We determined the age of sampled individuals, the age of the population and evaluated the effects of climate on tree growth. We obtained samples for dendrochronological analyses using destructive (seven individuals) and non-destructive methods. We cross-dated and built a chronology, correlating results with climatic factors. We sampled 0.6 ha of the population and separated individuals into diameter classes to determine age based on diameter/age ratio obtained through dendrochronological analyses. We obtained a chronology with individuals up to 34 years old, while in the population sample, the oldest individual was 54 years old. The factors that influenced growth during the study period were precipitation (positive correlation) and El Niño (negative correlation). E. fusca individuals seem to grow more during the period of highest precipitation, and El Niño events reduce precipitation in the Pantanal, resulting in a decrease in the growth of E. fusca individuals. We detected a decrease of young individuals in the last nine years, which seems to be related to the decrease in minimum flood levels. This indicates a future decline in the number of individuals. These results allow us to propose measures to protect these monodominant formations, which mainly involve avoiding further anthropic activities, that could reduce flooding levels.
气候因素会影响木本植物的建立和生长，但人们对这些因素如何影响湿地中的单优群落知之甚少。因此，我们想知道气候因素（如厄尔尼诺-南方涛动、降水和洪水）如何影响潘塔纳尔湿地中优势种红火球Erythrina fusca 的生长和建立。我们确定了采样个体的年龄、种群年龄，并评估了气候对树木生长的影响。我们使用破坏性（7 个个体）和非破坏性方法获取了树木年代学分析的样本。我们交叉定年并建立了一个年表，将结果与气候因素相关联。我们对 0.6 公顷的种群进行了采样，并将个体分为直径类，根据树木年代学分析得出的直径/年龄比来确定年龄。我们获得了一个有 34 岁个体的年表，而在种群样本中，最老的个体为 54 岁。在研究期间影响生长的因素是降水（正相关）和厄尔尼诺（负相关）。E. fusca 个体似乎在降水最多的时期生长得更快，而厄尔尼诺事件会减少潘塔纳尔的降水，导致 E. fusca 个体的生长减少。我们发现，在过去九年中，年轻个体数量减少，这似乎与最低洪水水位的下降有关。这表明未来个体数量将会减少。这些结果使我们能够提出保护这些单优群落的措施，主要包括避免进一步的人为活动，这些活动可能会降低洪水水位。
