Xingzhao Sun from the Vrije Universiteit Brussel (VUB) has conducted a significant study on the ecological interactions between herbivore dung and plant communities, shedding light on the roles of nutrients and microbial communities in ecosystems. The findings are published in the journal Ecology and Evolution.
Study Overview
Dr. Sun collected dung samples from five herbivore species—European bison, horse, fallow deer, rabbit, and Scottish Highland cattle—during a field study in Zuid-Kennemerland National Park, Netherlands, in early 2020. The samples were analyzed for nutrient content, including carbon, nitrogen, and phosphorus, as well as microbial community composition. The research also involved greenhouse and garden experiments to assess how different plant species responded to various types of dung.
Key Findings
One of the study’s main discoveries is that dung quality varies significantly among herbivore species. Dr. Sun noted that factors such as body size, digestive system type, and dietary preferences influence these differences. For example, rabbit dung is particularly high in nitrogen and has a unique microbial composition. This is due to rabbits’ digestive process, which includes coprophagy—re-ingesting their dung to maximize nutrient absorption. The nitrogen-rich dung from rabbits is especially beneficial for grass species.
However, Dr. Sun cautioned that no single type of dung is universally “best” for all plants. The impact of dung on plant communities is contingent on various factors, including specific plant-microbe symbiotic relationships and the nutrient needs of different plants. For instance, legumes, known for their nitrogen-fixing capabilities, tend to benefit more from dung with a lower nitrogen-to-phosphorus ratio, such as that from European bison or horses.
Implications
This research not only enhances our understanding of the ecological roles of herbivores but also emphasizes the complexity of their contributions to nutrient cycling in terrestrial ecosystems. The findings underscore the importance of considering specific plant needs and relationships when utilizing dung in gardening and agriculture.
Dr. Sun’s work provides valuable insights into how herbivore dung can be strategically used to improve plant health and ecosystem functioning, paving the way for more sustainable agricultural practices.