Effects of cattle stocking rates on nematode communities in south Florida

Ranch management practices aimed at cattle and pasture vegetation have the potential to impact other animals as well, including nontarget organisms. Soil-inhabiting nematodes are often used as bioindicators of nontarget effects because of their widespread occurrence and their diverse trophic habits and lifestyles. The effect of cattle stocking rates on nematode communities present in the soil was examined at the MacArthur Agro-Ecology Research Center in south-central Florida. Nematode abundance and richness (genera per sample) were not affected (P > 0.10) by cattle grazing in 2 different pasture types (tame grass and native) over three seasons. In general, populations of most nematodes showed strong seasonal responses, varying in numbers from year to year, possibly related to soil moisture levels. In comparison, the cattle stocking rates typically used in south-central Florida had little effect on soil nematodes, which were abundant nontarget organisms in this system.