The potential influence of understory management patterns on soil
nutrients and C:N:P stoichiometry in an urban forest
Abstract
Forest vegetation management plays an important role in maintaining soil
health and function. In highly-managed urban forests, the clearing of
understory vegetation has potential to cause loss of soil nutrients,
resulting in stoichiometric imbalances and a decrease in soil function.
Therefore, studying how to effectively manage understory to improve soil
quality is critical for stability and function of urban forest. Here, we
collected soil samples from a plantation forest in Zijin Shan National
Forest Park in two stands, each with three adjacent plots with different
understory management practices: one with high diversity natural
understory vegetation, another with low diversity managed understories
of ornamental groundcover (Reineckia carnea (Andr.) Kunth or Ophiopogon
bodinieri Levl.), and a third with cleared understory. Compared to plots
with natural understories, we found lower levels of soil total carbon
(C), total nitrogen (N), and some their fractions especially microbial C
and N, in plots with no understories. Correspondingly, ratios of soil C:
phosphorus (P) and N:P, and microbial C:N, were lower in the absence of
understories in one of the two stands. These influences were smaller
with ground-cover plants in both stands, particularly O. bodinieri. The
magnitude of these effects differed between the two stands, with greater
effects observed in the stand with higher soil C. While we cannot rule
out the effects of other influences on soil properties, these results
offer support for the hypothesis that human management practices affect
urban forest soil properties and microorganisms, and that appropriate
understory managements can alleviate these adverse influences.