How the abiotic factors affect the ecology of amphibians.

Abiotic factors influence the reproductive behavior of anurans. Although temperature and precipitation are the most studied, atmospheric pressure seems to be the only factor that indicates the predictability of meteorological changes in the near future. It is, therefore, likely to be perceived by anurans that initiate reproduction before rainfall. The anurans were monitored in the Municipality of Bocaina de Minas, State of Minas Gerais, Brazil, encompassing part of the Serra da Mantiqueira in the upper basins of Rio Preto and Rio Grande. Our objectives included analyzing species distribution by altimetry, determining the similarity of active species between river basins, testing the hypothesis that species within a river basin tend to vocalize in association, establishing the probability of species encounter in the sampling, categorizing the species’ constancy and dominance, analyzing the influence of temperature, relative humidity, rainfall and barometric pressure on the species’ vocal activity, and constructing a climogram to illustrate the range of these variables associated with the optimal, tolerant and rare occurrence of vocal activity. Of the 52 species sampled, 28 were common to both river basins. When categorizing species constancy, only eight species were constant, 18 were accessory, and 26 were accidental. Four species were classified as dominant, 43 as subdominant, and 22 as recessive. When analyzing the influence of abiotic factors on the reproductive activity of the local anuran community, the dominant predictive climatic factor is barometric pressure, followed by relative humidity, temperature, and rainfall.非生物因子（abiotic factors）会影响无尾目动物（anurans）的繁殖行为。尽管温度与降水是目前研究最多的非生物因子，但大气压力（barometric pressure）似乎是唯一可指示近期气象变化可预测性的因素。因此，那些能在降雨前启动繁殖行为的无尾目动物，大概率能够感知到这一环境信号。本研究于巴西米纳斯吉拉斯州（Minas Gerais）博卡伊纳-迪米纳斯市（Bocaina de Minas）开展，监测区域覆盖曼蒂凯拉山脉（Serra da Mantiqueira）的部分范围，该区域位于普雷图河（Rio Preto）与格兰德河（Rio Grande）的上游流域内。本研究的目标涵盖以下内容：按海拔高度分析物种分布情况；明确两大河流流域内活动物种的组成相似性；验证“同一河流流域内的物种倾向于同步鸣叫”这一假说；估算采样过程中各物种的遇见概率；对物种的恒常性与优势度进行分类；分析温度、相对湿度、降水量及大气压力对物种鸣叫活动的影响；构建气候图（climogram），以展示与鸣叫活动的最优发生、耐受发生及罕见发生情境相关的上述环境变量的取值范围。本次采样共记录到52个物种，其中28个物种在两大河流流域均有分布。对物种恒常性进行分类后，仅8个物种被划为恒常种，18个为伴生种，26个为偶见种。在优势度分类中，4个物种被归为优势种，43个为亚优势种，22个为稀有种。在分析非生物因子对当地无尾目类群繁殖活动的影响时，具备最强预测能力的气候因子为大气压力，其次依次为相对湿度、温度与降水量。