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在广西禄峰山林场16年生4种不同造林密度的湿地松试验林地内,对N、P、K、Ca、Mg、Cu、Fe、Zn、Mn9种养分元素的含量、积累、分配和生物循环以及它们与密度间的关系进行了研究。结果表明:湿地松林分中养分元素总积累量为127383~161588kg/hm2,树干约占60%,积累速率为11146~13339kg/hm2·a,高于杉木和马尾松,归还量仅有9043~10509kg/hm2·a,其周转期长,养分循环速率低,每生产1t有机物需要上述养分元素共1319~1481kg。可见湿地松具有高养分利用率、低循环速率的循环机理,经营过程中应处理好养地与用地的关系,才能防止林地退化。不同密度湿地松林以密度为3200株/hm2的生产力、养分积累量和吸收量最大,其养分利用率也最高。
Contents, Accumulation, Distribution and Biological Cycling of Nine Kinds of Nutrient Elements of N, P, K, Ca, Mg, Cu, Fe, Zn, Mn in 16-year-old Lufengshan Forest Farm in Guangxi Autonomous Region of China And their relationship with the density of the study. The results showed that the total accumulation of nutrient elements in Pinus elliottii was 127383 ~ 161588 kg / hm2, the trunk was about 60%, and the accumulation rate was 11146 ~ 13339 kg / hm2 · a, higher than that of Chinese fir and Pinus massoniana , The return of only 90 43 ~ 105 09kg / hm2 · a, the long turnaround time, nutrient cycle rate is low, the production of 1t organic matter requires a total of 1319 ~ 1481kg nutrient elements. It can be seen that Pinus elliottii has a cycling mechanism of high nutrient utilization rate and low circulation rate, and the relationship between the land for cultivation and land use should be properly handled in order to prevent forestland degradation. The productivity of 3200 plants / hm2 in different density Pinus elliottipes had the highest accumulation and absorption of nutrients and the highest nutrient utilization rate.