Organic Farming: A Practice for Conserving Arthropod Diversity and Soil Health in an Agroecosystem

Abstract

The sustainability of any agroecosystem depends on agricultural practices, arthropod diversity and soil health. This study assessed the diversity of arthropods and some soil parameters (soil organic matter (SOM), pH and Temperature (oC)) of three organic (ORGF) and conventional (CONF) farmlands at University of Nigeria, Nsukka. Each farm measured 10,000 m², 100 m apart was divided into four quadrants with pitfall traps (7.20 × 4.80 cm). Arthropods were collected weekly for three months and were preserved in a vial containing 70 % ethanol before identification. Soil samples were collected with auger at 10 cm depth, analyzed ex-situ for SOM and pH, in-situ for Temperature using standard protocols. A total of 172 arthropods belonging to six orders, 10 families, 19 genera and 15 species were observed with ORGF having higher number (n =113; 65.69%) than CONF (n = 59; 37.31%). Camponotus perrisii nigeriensis was the most dominant species (n =37; RA=21.51) while Anochetus siphneus, Gymnopleurus coerulescens and Gyna costalis were the least (n=1; RA=0.58). Hymenoptera were higher in ORGF (n=58) than CONF (n=9). Shannon-Wienner diversity index revealed that ORGF had more species diversity (H=2.21) than CONF (H=1.48) which varied significantly (p ≤ 0.05). Descriptive statistics showed that SOM was higher in ORGF (1.89 ± 0.34) than CONF (1.26 ± 0.45), pH higher in ORGF (5.44 ± 0.06) than CONF (2.34± 0.28) while Temperature was higher in CONF (27.23± 0.05) than in ORFG (24.09 ± 0.25). Diptera and Hymenoptera showed negative correlation with soil parameters while the rest showed positive. Organic farming had minimal effects on arthropods and soil parameters therefore it should be encouraged.