Long-term N addition reduced the diversity of Arbuscular mycorrhizal
fungi and understory herb of the Korean pine plantation in northern
With the development of agriculture and industry, the increase in
nitrogen (N) deposition has caused widespread concern among scientists.
Although emission reduction policies have slowed N releases in Europe
and North America, the threat to biodiversity cannot be ignored.
Arbuscular mycorrhizal (AM) fungi play an important role in the
establishment and maintenance of plant communities in forest ecosystems,
both their distribution and diversity have vital ecological functions.
Therefore, we analyzed the effects of long-term N addition on AM fungi
and understory herbaceous plants in Korean pine plantation in northern
China, measured the soil properties, AM fungal and herbaceous community
structure and diversity with different concentrations of NH4NO3
(0,20,40,80 kg N ha-1 year-1) applied for 7 consecutive years. The
results showed that long-term nitrogen fertilization affected soil
properties, decreased soil pH, increased soil ammonium content, and
caused significant fluctuations in P elements. Nitrogen application
improved the stability of soil aggregates by increasing the content of
GRSP (glomus-related soil protein); N addition changed the AM fungal
community composition, and Glomus genus was more adaptable to the acidic
environment treated with the highest nitrogen concentration; with the
increase of N treatment, The species of AM fungi and herbaceous plants
and the biomass of fine roots decreased. In summary, we concluded that
long-term understory application of different concentrations of N
altered soil pH, changed the distribution of N, P elements, and the soil
aggregate fractions, reduced AM fungal and herb diversity. The
importance of AM fungi in maintaining forest ecosystem diversity under
the pressure of global change was verified.