The stoichiometric characteristics of carbon, nitrogen, and phosphorus in soil aggregates of plantation with stand ages in the Rainy Area of Western China.

Understanding the variations in soil aggregate composition, as well as the contents and stoichiometry of organic carbon (C), total nitrogen (N) and total phosphorus (P), in the surface layer of plantations with different stand ages can provide a theoretical basis for the optimized management of plantations and the improvement of soil fertility in the Rainy Area of West China. With the dry-sieving method, we measured the contents of soil aggregates with different sizes in the 0-15 and 15-30 cm soil layers across plantations with five distinct developmental stages at Hongya Forestry Farm, Sichuan Province, including young stands (7 years old), middle-aged stands (13 years old), nearly mature stands (24 years old), mature stands (33 years old), and over-mature stands (53 years old). We further analyzed the C, N and P contents and ecological stoichiometric characteristics of soil aggregates.

[Effects of canopy on the redistribution of potassium and sodium ions in rainfall in Quercus acutissima and Camptotheca acuminata mixed plantation of the rainy area of western China].

The role of canopy in redistributing rainwater K and Na at different phenological stages (leafless stage, leaf expanding stage, frondent leaf stage and senesced leaf stage) was investigated in Quercus acutissima and Camptotheca acuminata mixed plantation in Mt. Lingyan of Dujiangyan city from December 2016 to November 2017. The concentrations of K and Na were 1.