Data on soil and root arbuscular mycorrhizal fungal biomass and community composition as well as environmental parameters in response to long-term deficiencies of nitrogen, phosphorus and potassium in a managed grassland

In this study, we evaluated how long-term nutrient deficiencies of phosphorus (P), nitrogen (N) and potassium (K) affects the abundance and community composition of AMF in a mountainous grassland. Besides, we investigated how the responses of AMF to those deficiencies were modulated by liming and the type of fertilizer addition (inorganic versus organic). We also assessed if the responses of AMF communities to long-term nutrient deficiencies and imbalances links to responses of plant communities and soil properties. Our study was carried out on a long-term nutrient deficiency experimental grassland site in Admont (Styria, Austria), established in 1946. Different fertilization treatments were applied for more than 70 years in a randomized block design, including numerous combinations of inorganic (P, N, K with/without lime) and organic (solid manure and liquid slurry) fertilizers. we collected both root and soil samples in July 2019 and measured AMF abundance in both soil and root samples by measuring 16:1ω5 neutral fatty acid (NLFA) biomarkers as well as AMF community composition by amplicon sequencing of the 18S rRNA genes. Moreover, the plant community composition was determined visually in 2015. The experimental plots were harvested in 2018 using a motorized bar mower and the green mass yield was determined directly in the field. A representative sample was then taken from each plot to determine the dry matter content. Additionally, we quantified edaphic factors such as pH, soil water content, N content, total dissolved nitrogen, dissolved organic N, ammonium, nitrate, total free amino acids, dissolved organic P, inorganic P, soil C content, dissolved organic C, soil N:P, and soil microbial C, N and P.