The design method for concrete waterfront amphibian ladder along streams

Abstract

How to balance environmental development and ecological conservation is one of the important issues of recent years. The main objective of this study is to investigate the behavioral patterns of amphibians on different substrates and slopes in order to provide necessary information to design a safe ecological amphibian ladder. Twenty Buergeria japonica, 20 Buergeia robustus, and 20 Rana swinhoana, were collected from the Wulai mountainous area in Taipei. The amphibians were divided into male and female samples, and their weight, body length, long jump, and high jump were tested. The effects of angle, material, temperature, and humidity on climbing ability were also discussed. The experimental results showed that the weight and body length of female frogs are larger than that of male frogs; the weight difference is 1.7-4 times; the body length is 0.9–2cm higher. The orders of high jump and long jump of the three species are: Buergeria japonica (♀)> Rana swinhoana(♀)> Buergeia robustus (♀)> Rana swinhoana (♂)> Buergeria japonica (♂)> Buergeia robustus (♂); Rana swinhoana (♀)> Rana swinhoana (♂)>Buergeria japonica (♂)> Buergeia robustus (♀)> Buergeria japonica (♀)> Buergeia robustus (♂). Comparison of climatic environments and climbing matrices showed that female frogs have better climbing ability than male frogs. The highest climbing value of Buergeia robustus in the low temperature and low humidity grass matrix 15°is 0.38 (×10−2N/g), that of Rana swinhoana in the low temperature and high humidity concrete matrix 15°is 0.25(×10−2N/g). In general, the climbing abilities of frogs perform worst in low temperature and low humidity environments. There, it is suggested that the above environment can be the climate condition for amphibian ladder design. Moreover, the maximum climbing angle of frogs can be used as useful information when designing an amphibian ladder. This study also suggests that if there are more than two species of frogs in a habitat, the designer should use a lower slope angle to design so that the frogs with different climbing abilities can relocate or escape through an ecological amphibian ladder.