SWEEPNET-COLLECTED INVERTEBRATE BIOMASS FROM HIGH-INPUT AND LOW-INPUTAGRICULTURAL FIELDS IN KANSAS

Various forms of tow-input sustainable agriculture (LISA) are becoming more common in the Plains States, but little research has been conduc ted to evaluate the suitability of LISA fields for avian populations, except as nesting habitat. Because invertebrates are the primary food source of many grassland birds, we compared invertebrate biomass assoc iated with LISA to that of conventionally farmed fields, grasslands, p astureland, and fallow fields. Sweepnets were used to collect inverteb rate samples from twenty 1.5-ha plots at 2 locations in eastern Kansas . Invertebrates were sorted to order (Orthoptera and Hemiptera to fami ly) and oven dried. Significantly higher biomasses (P < 0.05) of inver tebrates were collected from LISA, fallow, grassland, and pastureland plots than from conventionally farmed fields. Invertebrate biomasses v aried among different LISA treatments but few responses were significa nt because of limited replication of treatments and large variances. T wo- to nine-fold differences in biomasses of Orthopteran and Hemiptera n families were found among treatments. Incorporation of LISA into int ensive habitat-management programs could be beneficial to avian specie s relying on invertebrates as a food source.