Individual study: Species diversity, weed cover and seed numbers in the seed bank were higher in farming systems with reduced herbicide use than in the conventional farming system on three arable farms in Lower Saxony, Germany
Schmidt W., Waldhart R. & Mrotzek R. (1995) Extensification in arable systems: effects on flora, vegetation and soil seed bank - results of the INTEX-project. Tuexenia, 415-435
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Reduce fertilizer, pesticide or herbicide use generally
A replicated, controlled study in 1990-1994 on three arable farms in Lower Saxony, Germany (Schmidt et al. 1995) found significantly higher plant species diversity, weed cover and seed numbers in the seed bank in an ‘integrated’ farming system with a 50% reduction in chemical inputs (fertilizer, pesticides/herbicides) than in a conventional farming system. Species richness, weed cover and seeds in the soil were also higher in the extensive (no input) farming system than in the conventional system, but did not differ from the integrated farming. Crop cover, however, was significantly reduced only in the extensive farming system. Thus, a 50% reduction in herbicide use was the most efficient way of combining the economic interests of agriculture (crop yield) with weed protection. On three farms, field trials with three different farming systems were compared: conventional farming (normal pesticide/herbicide use and fertilization), integrated farming (50% reduction in pesticide/herbicide use, 25-40% reduction in mineral fertilization), and extensive farming (no pesticide/herbicide use, no mineral fertilization). Plants were monitored several times a year in four permanent plots (10 x 10 m) on two of the farms. Soil samples (0-5 cm and 5-30 cm depth) were taken in March 1990 and 1993 on all three farms. Seeds were germinated in the laboratory for 20 months after different growth stimulations. This study was part of the same project (INTEX – Integrated Farming and Extensification of Agriculture) and was carried out in partly the same research site as (Hasken & Poehling 1995, Krooss & Schaefer 1998).