Abstract
Litters of reproductive organs have rarely been studied despite
their role in allocating nutrients for offspring reproduction. This study
determines the mechanism through which flower litters efficiently increase
the available soil nutrient pool. Field experiments were conducted to collect
plant litters and calculate biomass production in an alpine meadow of the
eastern Tibetan Plateau. C, N, P, lignin, cellulose content, and their
relevant ratios of litters were analyzed to identify their decomposition
features. A pot experiment was performed to determine the effects of litter
addition on the soil nutrition pool by comparing the treated and control
samples. The litter-bag method was used to verify decomposition rates. The
flower litters of phanerophyte plants were comparable with non-flower
litters. Biomass partitioning of other herbaceous species accounted for
10–40 % of the aboveground biomass. Flower litter possessed
significantly higher N and P levels but less C ∕ N, N ∕ P,
lignin ∕ N, and lignin and cellulose concentrations than leaf litter. The
litter-bag experiment confirmed that the flower litters of
Rhododendron przewalskii and Meconopsis integrifolia
decompose approximately 3 times faster than mixed litters within 50 days. Pot
experiment findings indicated that flower litter addition significantly
increased the available nutrient pool and soil microbial productivity. The
time of litter fall significantly influenced soil available N and P, and soil
microbial biomass. Flower litters fed the soil nutrition pool and influenced
nutrition cycling in alpine ecosystems more efficiently because of their
non-ignorable production, faster decomposition rate, and higher nutrient contents compared with non-flower litters. The
underlying mechanism can enrich nutrients, which return to the soil, and
non-structural carbohydrates, which feed and enhance the transitions of soil
microorganisms.
Citation
ID:
148205
Ref Key:
wang2016biogeosciencesflower