Caliman A, Carneiro L S, Santangelo J M, Guariento R D, Pires A P F, Suhett A L, Quesado L B, Scofield V, Fonte E S, Lopes P M, Sanches L F, Azevedo F D, Marinho C C, Bozelli R L, Esteves F A, Farjalla V F
Departamento de Ecologia, Instituto de Biologia, Prédio do CCS, Universidade Federal do Rio de Janeiro – UFRJ, Ilha do Fundão, CP 68020, CEP 21941-590, Rio de Janeiro, RJ, Brazil.
Braz J Biol. 2010 Oct;70(3 Suppl):803-14. doi: 10.1590/s1519-69842010000400011.
Temporal coherence (i.e., the degree of synchronicity of a given variable among ecological units within a predefined space) has been shown for several limnological features among temperate lakes, allowing predictions about the structure and function of ecosystems. However, there is little evidence of temporal coherence among tropical aquatic systems, where the climatic variability among seasons is less pronounced. Here, we used data from long-term monitoring of physical, chemical and biological variables to test the degree of temporal coherence among 18 tropical coastal lagoons. The water temperature and chlorophyll-a concentration had the highest and lowest temporal coherence among the lagoons, respectively, whereas the salinity and water colour had intermediate temporal coherence. The regional climactic factors were the main factors responsible for the coherence patterns in the water temperature and water colour, whereas the landscape position and morphometric characteristics explained much of the variation of the salinity and water colour among the lagoons. These results indicate that both local (lagoon morphometry) and regional (precipitation, air temperature) factors regulate the physical and chemical conditions of coastal lagoons by adjusting the terrestrial and marine subsidies at a landscape-scale. On the other hand, the chlorophyll-a concentration appears to be primarily regulated by specific local conditions resulting in a weak temporal coherence among the ecosystems. We concluded that temporal coherence in tropical ecosystems is possible, at least for some environmental features, and should be evaluated for other tropical ecosystems. Our results also reinforce that aquatic ecosystems should be studied more broadly to accomplish a full understanding of their structure and function.
时间相干性（即预定义空间内生态单元中给定变量的同步程度）已在温带湖泊的若干湖沼学特征中得到体现，这使得能够对生态系统的结构和功能进行预测。然而，在热带水生系统中，季节间气候变率不太明显，几乎没有时间相干性的证据。在此，我们利用对物理、化学和生物变量的长期监测数据，来测试18个热带沿海泻湖之间的时间相干程度。在这些泻湖中，水温的时间相干性最高，叶绿素a浓度的时间相干性最低，而盐度和水色的时间相干性居中。区域气候因素是导致水温与水色出现相干模式的主要因素，而景观位置和形态特征则解释了泻湖之间盐度和水色的大部分变化。这些结果表明，局部（泻湖形态）和区域（降水、气温）因素通过在景观尺度上调整陆地和海洋补给，来调节沿海泻湖的物理和化学条件。另一方面，叶绿素a浓度似乎主要受特定局部条件的调节，导致生态系统之间的时间相干性较弱。我们得出结论，热带生态系统中的时间相干性是可能的，至少对于某些环境特征而言是如此，并且应该对其他热带生态系统进行评估。我们的结果还进一步表明，应该更广泛地研究水生生态系统，以全面了解其结构和功能。
