Functional diversity is important to maintain ecosystem functioning. Species with different ecomorphological traits may display distinct functional roles in ecosystems. Accordingly, functionally extreme species are more important as they can exhibit specific strategies. However, little is known about the distribution patterns of functionally extreme species at a local scale and whether the prior extinction of extreme species can cause significant effects on functional diversity. In addition, no empirical studies have been conducted on the microhabitat determinants of extreme species to maintain the functional diversity. This study collected 1470 tadpoles belonging to 6 families and 20 anuran species. These species were subsequently divided into 65 functional entities based on their developmental stages to incorporate intraspecific traits variability. As a result, we detected seven extreme functional entities, accounting for 10.7% of the total number of entities. Moreover, the prior extinction of extreme entities can lead to a significant decrease in functional diversity compared with the random extinction of entities. Microhabitat variables such as conductivity, water depth, and current velocity determined the distribution of extreme entities. Although the functionally extreme entities only represented a small proportion of the total number of tadpoles, they played irreplaceable roles in maintaining functional diversity. Their extinction may induce high functional vulnerability in tadpole communities. Therefore, anuran species with extreme tadpole traits need to be projected for amphibian conservation.

中文翻译：

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揭示功能极端的蝌蚪类型对功能多样性的重要性：温带山地溪流的案例研究

功能多样性对于维持生态系统功能很重要。具有不同生态形态特征的物种可能在生态系统中发挥不同的功能作用。因此，功能极端的物种更为重要，因为它们可以表现出特定的策略。然而，人们对局部范围内功能极端物种的分布模式以及极端物种的先前灭绝是否会对功能多样性产生重大影响知之甚少。此外，还没有对极端物种的微生境决定因素进行实证研究以维持功能多样性。本研究采集了无尾目动物6科20种1470只蝌蚪。这些物种随后根据其发育阶段分为 65 个功能实体，以纳入种内性状变异性。结果，我们检测到 7 个极端功能实体，占实体总数的 10.7%。此外，与实体的随机灭绝相比，极端实体的先验灭绝可能导致功能多样性显着下降。电导率、水深和流速等微生境变量决定了极端实体的分布。尽管功能极端的实体只占蝌蚪总数的一小部分，但它们在维持功能多样性方面发挥着不可替代的作用。它们的灭绝可能会导致蝌蚪群落的高度功能脆弱性。所以，