Soil nematodes associated with different land uses in the Los Tuxtlas Biosphere Reserve, Veracruz, Mexico

Modification of above-ground land use leads to many changes in the below-ground rhizosphere. A study was conducted of soil nematodes and their diversity associated with different land uses in the Biosphere Reserve Los Tuxtlas, Mexico. Three sites were selected to investigate 4 types of land uses: natural forest, secondary forest, pasture, and maize fields. Total abundance of nematodes and estimators based on generic and diversity indices were assessed and compared between the 4 land uses and sites. Fifty-three families and 124 genera of nematodes were identified from the study area. The dominant families were Criconematidae, Hoplolaimidae, Cephalobidae, and Tylenchidae, and the most abundant genera in this study were Helicotylenchus, Discocriconemella, Tylenchus, Steinernema and Mesocriconema. The greatest nematode abundance, generic richness, and diversity were found in natural forest, closely followed by secondary forest. Intensive (largely monocrop) agricultural systems, represented by maize fields and pasture, had low generic richness and significantly less diversity than non-disturbed systems. Most of the estimators and indices were useful in showing the significant effects of different land uses on soil nematodes in Los Tuxtlas, Mexico. This study is the first of its type to be carried out in the Biosphere Reserve Los Tuxtlas, being the first report of soil nematodes that shows the effects of the land use changes that have been made in recent years. (C) 2017 Universidad Nacional Autonoma de Mexico, Instituto de Biologia.