From the perspective of land use and climate, the number and diversity of insects in the world are declining
however, these findings seem to have weaknesses, said Professor J ö RG m ü ller, an animal ecologist from the Julius Maximilians Universit ä t w ü rzburg (JMU) Biological Center in Bavaria, Germany. Among them, the basic research so far can not well represent the diversity of insect species, or only consider short-term and small areas. A research team from the Bavarian landklif network, coordinated by JMU, now hopes to remedy this deficiency. The results of the study have been published in the journal Nature communications. They show that urbanization is another key factor leading to the overall decline of insects
the study was conducted at 179 locations from low altitude to high altitude
from lower Franken to Upper Bavaria, researchers placed traps in the spring of 2019 to collect flying, crawling and jumping insects. These traps are located in 179 locations in the Bavarian Forest and the Alps, from lowlands to more than 1100 meters above sea level. They are located in forests, grasslands and fields and settlements, embedded in semi natural, agricultural and urban landscapes. The researchers emptied the trap every 14 days throughout the vegetation period. They determined the biomass of captured insects and identified individual species using DNA sequencing
insects benefit from higher temperatures
J ö RG m ü ller explains: “In this study, we were able to isolate the effects of climate and land use on insects in the landscape of central Europe for the first time. Interestingly, local temperature and annual temperature have only a positive impact on the biomass and diversity of insect populations. On the other hand, land use forms have different effects on biomass and diversity. We observed the largest difference in insect biomass between semi natural and urban environments. In cities, biomass is 42% lower. Compared with semi natural habitat, insect diversity in agricultural environment is 29% lower. “There are even 56% fewer endangered species in agricultural areas,” said Johannes uhler, the first author of the study and a JMU doctoral student. ”
uhler concluded:” these comparative patterns of biomass and species diversity are an important warning signal for researchers: for insect monitoring, people should not conclude that the decline of biomass also means the decline of species diversity, and vice versa. “Based on their new findings, JMU researchers suggest creating more green space in the urban environment to increase the biomass of insects. The existing agricultural environment plan should be further expanded to improve biodiversity and promote forest protection.
Bavaria landklif research network was established in 2018 and is active in semi natural, agricultural and urban areas in Bavaria’s five climate regions In the urban landscape: from the dry and warm areas of lower Franken state to the high-altitude areas of Bavarian Forest and bechtesgaden National Park. The purpose is to determine solutions to mitigate climate change and adapt to changing climate conditions. The coordinator of the network is Professor Ingolf steffan dewender of JMU biological center. The free state of Bavaria provides 2.6 million euros for the network