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Environmental Risks of the Pesticide Use in Agrocenoses and Their Management

Lishchuk Alla, Parfenyk Alla, Horodyska Іnna, Boroday Vira, Ternovyi Yurii, Tymoshenko Liudmyla

Journal of Ecological Engineering

2023

Vol. 24, nr 3

199--212

The article is devoted to the development of methodical approaches to the management of environmental risks due to pesticide contamination of agrocenoses. An assessment of ecological risks due to the use of pesticides was carried out at the scientific research field of the Skvirskaya research station of organic production of the IAP of the National Academy of Sciences during the growing seasons of 2019–2021. The methods of assessing the ecological risks of potential pesticide contamination of agrocenoses based on the indicators of the agroecotoxicological index (AETI) and the ecotoxic impact of harmful substances (E) were used on the natural environment. It was shown that the level of environmental risk due to the use of pesticides in the research field of the station according to the weighted average indices (AETI) is characterized as low – risk, and the environmental risk due to the pesticides using is minimal. According to indicators of ecotoxicity (E), the pesticides that were used are characterized as having a low potential ecotoxic risk of impact on agrocenoses of cultivated plants. However, the total pesticide ecotoxicological load (ΣЕ = 0.425 compared to the standard EDDT = 1) indicates the possibility of disruption of ecological connectivities in the agroecosystem. One of the elements of environmental risk management can be the assessment of the pesticide load on agroecosystems and considering of the territory ability to self-clean. In order to minimize the environmental risks of pesticide contamination of agrocenoses, measures should be taken to regulate the use of chemical plant protection agents. This can be done by banning or limiting the use of pesticides that have a high level of ecotoxicity and are persistent in the soil. This will contribute to increasing the ecological safety of agro-ecosystems and the natural environment.

Illecebrum verticillatum L. - endangered species in agrocenoses of Eastern Poland : assessment of ecological and genetic indicators for protection goals

Skrajna T., Kubicka H., Rzymowska Z.

Polish Journal of Ecology

2012

Vol. 60, nr 3

577-589

A rapid decrease in floristic biodiversity of agrocenoses has been observed in Europe for a half of century. A dynamic intensification of processes of crop production is considered one of the major reasons for shrinking of occurrence acreage and population number, or even extinction of numerous species with narrow ecological niche and high sensitivity to herbicides. These unfavourable transformations contribute to the gene pool restriction and necessity of species conservation. A representative of that group of plants is Illecebrum verticillatum (Caryophyllaceae) - a rare species endangered due to extinction in many European countries. Results of a study on decline of communities with Illecebrum verticillatum at the most northeastward sites in the Kałuszyn Upland (Podlasie Lowland, Eastern Poland) are presented. Observations were made on permanent plots for three periods (I - the years 1994-1997, period II - the years 2002-2004 and period III - the years 2008-2010) over the last 17 years. The material studied consisted of 136 phytosociological releves made by Braun-Blanquet method. Changes in phytocenoses with Illecebrum verticillatum were analysed and the habitat factors responsible for regression of these phytocenoses were identified. The degree of endangering of Illecebrum verticillatum in the area studied was evaluated on the basis of the frequency of occurrence, population abundance and genetic variation at the level of storage proteins in seeds by the modified SDS-PAGE method. Comparison of phytocenoses from different periods revealed a number of qualitative and quantitative differences. The number of sites of occurrence as well as population abundance of Illecebrum verticillatum have drastically decreased. Changes in the contribution of indicatory species (according to Ellenberg) were noted. In periods II and III a decrease in the contribution of hygrophilous and acidophilous species and an increase in that of nitrophilous species was observed. Significant changes in the structure of communities were confirmed by the calculated similarity indices (the most pronounced differences were observed between periods I and III). The phytocenoses were transformed towards degraded floristic composition, manifested by a decrease in the number of species in a plot, decrease in species diversity and increase in the index of domination. A significant increase in pH and nitrogen content at the habitats studied was noted. The phytocenoses reveal a replacement of nitrophilous for the eurytopic species. The factors having the strongest restricting effect on the occurrence of communities with Illecebrum verticillatum in the areas studied include: changes in the structure of agricultural use of land, increase in the contribution of maize in the structure of crops and intensification of production. At present 6 sites with Illecebrum verticillatum remain in the study area about 260 km2 (Kałuszyn Upland, Central-eastern Poland). Electrophoretic analysis of storage proteins in seeds of this species from these sites has shown high genetic similarity of these populations, irrespective of the distances between them (0-19% diversity among six the remaining populations). The diminished genetic pool of Illecebrum verticillatum population in this area indicates a need for the protection of this species.