Influence of agricultural management form on the species structure of harvestman (Opiliones) communities

The paper is aimed at evaluation of the influence of two different agricultural management forms on harvestman (Opiliones) communities structure in relation to the optimization of land use on the model territory of Agricultural Cooperative (AC) Očová (Central Slovakia). The research was carried out using pitfall trapping through growing seasons from 2005 to 2007. Harvestmen were captured at four pairs of sites (8 sites in total). For each pair of sites the cultivation of the same crop with application of two different forms of agricultural management (conventional form and sustainable form with basic sustainable agro-environmental scheme) was characteristic. In total, 667 individuals of 8 species of the Phalangiidae family were captured during the research. The research results confirm the influence of management form on the structure of harvestman communities only partially. The obtained data indicate that the management form plays a significant role, especially in such agrocoenoses, in which the same crop is cultivated for several years (e.g., sites with alfalfa or permanent lawn), i.e., on the sites without ploughing or use of other similar agrotechnical measures. In these cases, the sites with the sustainable agro-environmental scheme showed higher diversity and equability of harvestman communities than the sites with the conventional form of agrotechnical management. Harvestman communities structure on sites with crop rotation and repeated ploughing was more influenced by additional factors than by the agricultural management form.