Supervisors:

prof. dr hab. Piotr Nowicki (piotr.nowicki@uj.edu.pl)
dr Joanna Kajzer-Bonk

Institute of Environmental Sciences
Institute of Zoology and Biomedical Research

Background information:

Lawns constitute a large part of urban areas, but their intensive maintenance is in contradiction to global challenges of mitigating climate change and biodiversity loss. Considered to be functional and aesthetic, intensive mowing prevents plants from flowering and leads to the formation of a low, compact lawn. This results in expensive and labor-intensive management, requiring irrigation, fertilization, use of herbicides, and frequent mowing generating noise, dust, and greenhouse gases. There is an urgent need to create modern solutions to slow down the negative consequences of anthropogenic pressure in urbanized areas that also affect human well-being. Previous research revealed that intensive mowing is harmful to biodiversity, but there is still a lack of synthetic studies into the impact of mowing regime on complex environmental parameters. While non-intensive mowing is typically considered beneficial for biodiversity, in a highly transformed urban environment it may potentially increase the probability of exposure to ticks and/or create a gateway to the invasion of undesirable alien species that drastically reduce native biodiversity. The goal of this project is to determine the benefits and risks associated with different mowing frequencies.

The main question to be addressed in the project:

What mowing regime is optimal for urban lawns to support their biodiversity and ecosystem services?

Information on the methods/description of work:

A large-scale experiment has been established within the 3^rd JU Campus, with 64 experimental paired plots in the mowing system of 2 vs. 4, 6, 8 cuts per year or 1 cut every two years. The environmental parameters to be examined in three consecutive seasons include 1) microhabitat and microclimatic conditions expressed by temperature and physicochemical properties of the soil; 2) activity of soil mesofauna; 3) aboveground biodiversity of vascular plants and invertebrates (wild bees, butterflies, spiders, orthopterans); 4) exposure to ticks; 5) potential risk of encroachment of invasive alien plants. Additionally, a questionnaire survey of four focal stakeholder groups (society, NGOs, business, and public sector) will be conducted to identify potential social fears and prejudices concerning extensive lawn maintenance.

Additional information (e.g Special requirements from the student):

The PhD project is a part of the running project “To mow or not to mow?”. Requirements: (1) MSc in biology, ecology, or related field; (2) basic expertise in statistical analysis; (3) fluency in English; (4) communication and organizational skills.

Place/name of potential foreign collaborator:

Helmholtz Center for Environmental Research UFZ Halle, Germany / Josef Settele

References:

[1] Ignatieva & Hedblom (2018) An alternative urban green carpet. Science 362:148–149.

[2] Sehrt et al. (2020) Less is more! Rapid increase in plant species richness after reduced mowing of urban grasslands. Basic Appl Ecol 42:47–53.

[3] Watson et al. (2019) Ecological and economic benefits of low-intensity urban lawn management. J Appl Ecol 57: 436–446.