| Abstract [eng] |
Invasive plants threaten biodiversity by outcompeting native plant species and some also pose a risk to human health. This study provides new data on the spread and impact of invasive plants on native plants in Mažeikiai. The focus of the work is the distribution of invasive plants and their impact on native plants in Mažeikiai. The aim is to determine the distribution of invasive plants in Mažeikiai, their impact on native plants and the necessary control measures. Field studies started in May 2023 and completed in September. The invasive plant species diversity and distribution in Mažeikiai was determined by a route method. The coordinates, area of location, projected cover of invasive plants were recorded, the biotope was determined, the location was assessed for mowing and the intensity of the land use was determined. The impact of Solidago canadensis, Rumex confertus and Acer negundo on native vegetation was determined using quadrat and transect methods. A total of 8 invasive plant species and 267 locations were detected. In terms of plant cover, Robinia pseudoacacia covered 139,30 m2, Lupinus polyphyllus – 0,30 m2, Solidago canadensis – 673,40 m2, Rosa rugosa – 360,30 m2, Heracleum sosnowskyi – 52,35 m2, Rumex confertus – 400,40 m2, Acer negundo – 5103,57 m2, Phalacroloma septentrionale – 35,60 m2. The highest percentage of the invasive plant locations was found in lawns, grasslands and shrubs – 42%, 28% and 17% respectively; in well-maintained area – 49%; 56% of the locations are mown. Invasive plants have been found to reduce the diversity of native plants in the areas where they are established: the number of species has decreased by 67% and the plant diversity index by 38% in the case of Solidago canadensis, by 7% and 1,8% in the case of Rumex confertus and by 3,7% to 15% and 4% to 8% in the case of Acer negundo. For Solidago canadensis, the projected cover was found to be inversely proportional to the number of native species (rs=-0,92; p<0,05). To avoid the spread of invasive plants and the increased costs of delayed action, it is recommended to apply digging and chemical treatment for the control of Acer negundo, Rosa rugosa and Robinia pseudoacacia, for Rumex confertus, Solidago canadensis and Phalacroloma septentrionale – mowing, for Lupinus polyphyllus – digging and to control Heracleum sosnowskyi – the use of chemical treatment and mowing. Provide for at least 5 years of monitoring at these sites. |
