Soil microarthropods as indicators of soil quality of tropical home gardens in a village in Kerala, India

The cosmopolitan distribution of soil microarthropods and their various degrees of adaptation make them suitable tools for assessing soil ecosystem health. In this study, the microarthropod abundance of 25 home gardens in Kerala state located in South West coast of India was studied during summer and north east monsoon season of 2014. The soil microarthropods were categorized into six groups: collembola, coleoptera, hymenoptera, araeneae, acari and diplopoda. Their numbers varied from 0 to 28 per 1000 cm3 and were more abundant in the rainy season than in summer. The occurrence of these microarthropods was positively correlated to soil moisture and organic carbon and had negative correlation to soil temperature and soil pH. The presence of eu-edaphic and epi-edaphic microarthropod fauna was used to derive the soil quality index of each home garden and soil quality classes were defined. Out of the 25 home gardens, two were of good quality, 21 were of medium quality and two were of poor quality. The study supports the scope of applying the indicator value of soil microarthropods in future studies related to soil quality, management and conservation of tropical home garden ecosystems, which are facing threats of removal of canopy and unscientific land management practices.