Evaluating Sampling Techniques for Soil Dwelling Arthropod Species Composition and Abundance in University of Uyo, Uyo, Akwa Ibom State, Nigeria

Abstract

This study compared two sample approaches, pitfall traps and the Berlese-Tullgren extractor funnel, for the collection of soil-dwelling arthropod species at the University of Uyo between May and August 2023. For the study, three (3) sampling areas were selected: the Faculties of Science, Agriculture, and Engineering. The following physico-chemical parameters of the soil were measured: pH, temperature, dissolved oxygen, conductivity, chloride, nitrate, phosphate, sulphate, and nitrite. Pitfall traps made of plastic containers measuring 27cm deep with a mouth diameter of 30cm and containing 4 – 5% formalin were buried in 30cm deep dug soil. Berlese-Tullgren extractor funnels with 100watt bulbs were built from a 20L C-way plastic water container and screened with a 1mm mesh net. The results of the soil physico-chemical parameters revealed that the variables differed significantly between sampling sites at p≤0.05. Sixty-two (62) species of soil-dwelling arthropods were collected and classified into thirteen (13) orders and three classes, Insecta, Arachnida, and Diplopoda. The orders Orthoptera, Hemiptera, Coleoptera, Hymenoptera, and Lepidoptera comprise a large majority of the soil-dwelling arthropod species that were collected with pitfall traps. The order Diptera was unique to the Berlese-Tullgren extractor funnel, and diplopodans collected with the Berlese-Tullgren extractor sample technique were higher than those collected with the pitfall trap. A comparative analysis of the data on species diversity, individual and relative abundance, and soil-dwelling arthropod species revealed that the pitfall trap performed better than the Berlese-Tullgren extractor funnel in terms of collection efficiency. The likelihood of underrepresenting an order was eliminated since the pitfall trap sample approach, which is more efficient than the Berlese-Tullgren extractor funnel, complemented each other.