Invertebrate numbers rise 99 per cent after reducing grassland mowing
German researchers found that limiting land use at 45 sites significantly increased invertebrate abundance over three years, according to the Times of India.
German researchers found that reducing land use in grasslands led to a 99 per cent increase in invertebrate abundance after three years, according to a report by the Times of India. The study, published in ScienceDirect, involved testing 45 sites across the Schwäbische Alb, Hainich-Dün and Schorfheide-Chorin regions.
The experiment, which began before the 2020 vegetation period, involved plots that were mown only once a year in August or September. These plots received no grazing or fertilisation, unlike the regularly managed control plots. Invertebrate abundance rose by 41 per cent after one year and reached 99 per cent after three years.
The researchers used a custom-built suction sampler to collect invertebrates in May 2021 and May 2023. The study excluded ants, mites and springtails from abundance figures. While 479 unique species were identified in 2021, the authors noted that species diversity did not differ significantly between the reduced land-use plots and the control plots.
The scale of the increase depended on how the surrounding grassland was managed. The authors stated that the impact was more significant on sites that had been heavily fertilised and where the surrounding area was not mown as frequently. The effects were also larger when the single annual mowing was done at a higher cutting height.
The researchers identified limitations in the study, including a lack of biomass data and the inability to assess diversity in 2023 due to budget constraints. The study concluded that further research is needed to see how these outcomes develop over time through permanent land-use reduction.