Publication Date:
2016-05-01
Description:
Masson pine caterpillar (MPC, Dendrolimus punctatus Walker) outbreaks periodically occur in Masson pine (Pinus massoniana Lamb.) plantations in southern China; however, their effects on nutrient cycling remain unclear. In 2011, an MPC outbreak occurred in pine plantations with different stand densities, which facilitated a comparison of nitrogen (N) and phosphorus (P) cycling dynamics. Monitoring of soil and foliar nutrients from pre- to post-outbreak years (i.e., from 2010 to approximately 2012) indicated that soil NO3–-N concentration and fluxes were higher after the outbreak in low-density plantations, whereas soil NH4+-N and P availability varied minimally and were not different between the high- and low-density sites. Pine foliage responses to the MPC outbreak were dependent on stand density. At the high-density site, foliar N increased by 40% with an increase of 25% in N resorption efficiency and by approximately 200%–300% in P resorption efficiency, whereas there was an increase of 50% N concentration, a 65% increase in N resorption efficiency, and a 〉500% increase in P resorption efficiency at the low-density site. Overall, soil nutrients were higher in low-density than high-density plantations, whereas leaf nutrient resorption had the opposite results after an MPC outbreak. The effects of a periodic MPC outbreak could increase plant N:P stoichiometry in these plantations, particularly in the denser stands.
Print ISSN:
0045-5067
Electronic ISSN:
1208-6037
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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