JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 1993, Vol. 17 ›› Issue (03): 1-8.doi: 10.3969/j.jssn.1000-2006.1993.03.001

    Next Articles

SEASONAL CHANGES OF NUTRIENT CONCENTRATIONS AND NUTRIENT INTERACTIONS IN NEEDLES OF CHINESE FIR PLANTATIONS

Zhong Anliang Xiong Wenyu   

  1. Department of Forestry
  • Online:1993-09-18 Published:1993-06-18

Abstract: Current or 1 - year - old needles from dominant , average and depressed trees in different Chinese fir stands at Fudong Branch of Fengshushan Forest Station were sampled in different seasons in 1988, and nutrient concentrations of N, P, K, Ca, Mg and S in needles were analyzed to reveal the nutritional characteristics, nutrient dynamics and the interaction between various nutrients in the Chinese fir plantations. The nutritional status in the Chinese fir plantations was closely related to stand age and site quality. There were similar seasonal changes of nutrient concentrations in 5-, 10-, and 20-year-old Chinese-fir stands. Total N, P, K, and Mg were lowest and total S was lower during bud flush; total N in needles of 5-year-old stands and total P, K, and S in needles of 5-, 10-, and 20-year-old stands were highest during the first fast growing season (mid-June) total N in needles of 10-and 20-year-old stands and total Mg in needles of 5-, 10-, and 20-year-old stands were highest during the second fast growing season (mid-September). Total Ca in needles was lower during fast growing seasons, especially the first fast growing season, and higher or highest during bud flush or pre-dor-mancy. There was a significantly positive interaction between N and P nutrition in Chinese fir plantations and a positive relationship between N and S metabolism but significant antagonism between K, Ca and Mg. On the windward slope, N and P nutrition in the Chinese fir plantations were depressed, total Ca and total Mg in needles declined but K nutrition was strengthened.