A comparison of ground beetle assemblages (Coleoptera: Carabidae) in conventionally and ecologically managed alfalfa fields

Abstract

From 2007-2011, the occurrence of ground beetles (<em>Coleoptera</em>: <em>Carabidae</em>) was studied using emergence traps in two differently managed alfalfa fields in the Czech Republic - a conventional and an ecological production system. In total, 784 specimens of ground beetles representing 58 species were trapped in these two alfalfa fields in South Moravia. A slightly higher number of specimens were trapped in the conventionally managed than in the ecological alfalfa stand (404 <em>vs</em> 380, respectively). In the conventionally managed alfalfa stand, the number of species was also higher than in the ecological stand (45 <em>vs</em> 40, respectively). With the exception of 2007 and 2009, Simpson’s indices of diversity were higher in the conventional stand than in the ecological in all study years. Shannon’s index was higher in the conventional alfalfa field in 2008, 2009, and 2011. Regarding distribution, species classified into group E (<em>i.e.</em>, those without special demands on the type and quality of their habitat) dominated in both types of management throughout the experimental period. The incidence of species classified into group R (<em>i.e</em>., those with narrow ecological amplitude) was very low;<em> i.e</em>., only four species. These ground beetle species are included in the Red List of Threatened Species of the Czech Republic, and all of them (<em>i.e</em>. <em>Acupalpus</em> <em>suturalis</em>, <em>Calosoma</em> <em>auropunctatum</em>, <em>Cicindela</em> <em>germanica</em> and <em>Ophonus</em> <em>cribricollis</em>) are listed as vulnerable.

Continuous Agrochemical Treatments in Agroecosystems Can Modify the Effects of Pendimethalin-Based Herbicide Exposure on Immunocompetence of a Beneficial Ground Beetle

“…Herbicides such as atrazine, simazine, paraquat and glyphosate are well known to have effects on carabid population dynamics [63][64][65][66][67][68] or to cause mortality [8,69,70]. However, the studies on these subjects have mainly focused on indirect effects from the organism to community level related to food depletion or habitat modification [1].…”

Regulation of the abundance of clover seed weevils, Apion spp. (Coleoptera: Curculionidae) in a seed stand of red clover (Trifolium pratense L.)

“…The effectiveness of this product can be especially influenced by weather conditions at the time of application, as it is known that efficacy of pyrethroids is markedly influenced by high temperatures and solar UV radiation (Kolařík & Rotrekl, 2012b;Ma et al, 2012). These products can completely lose their efficacy, enabling insect pests to continue to survive and feed, so that a grower expecting such an application to prevent seed yield losses will not be successful if the application takes place on an unsuitable date.…”

“…These insecticides' efficacy is not dependent on weather conditions, and they show good residual activity on both adults and larvae, even at higher temperatures. Pyrethroids are only contact insecticides, and their residual effect on adults is relatively short (Kolařík & Rotrekl, 2012b;Lundin et al, 2012).…”