会同广坪林区降雨和杉木林内雨的养分含量

Nutrient Contents in the Rainfall inside and outside the Stands of Guangping Forest Zone, Huitong

对会同广坪林区的大气降雨、水库水、小河水及杉木林内雨的养分含量进行了 5个水文年的定位监测 .结果表明 :水库水、小河水中的 10种养分元素 N、P、K、Ca、Mg、Fe、Cu、Mn、Zn、Si,有的含量高于降雨 ,而有的含量低于降雨 ;降雨中各养分元素按含量高低排列顺序为 K>Zn>Ca>Org-N>NH4 -N>NO3-N>Si>Mg>Mn>P;林内雨中 P、K、Ca、Mg、Fe、Cu、Mn、Zn、Si元素含量均比降雨高 ;从林冠层淋洗的养分量为 79.475 kg·hm- 2 a- 1 ;从林内雨直接进入林地土壤的养分总量为 161.95 7kg· hm- 2 a- 1 ,其中以Ca元素最高 ,为 73 .71kg· hm- 2 a- 1 ,为外界补充杉木幼林地土壤养分的主要来源 ,对加速杉木林的养分循环和促进林木生长 ,具有重要的生态作用 .该项研究可为杉木林的持续经营 ,生态环境保护提供科学依据 .

The nutrient contents in the rainfall inside and outside (the near reservoir, the near little rivers) the stands of Guangping Forest Zone, Huitong, have been monitored for 5 consecutive hydrological years. The results indicate that the contents of 10 nutrient elements (N, P, K, Ca, Mg, Fe, Cu, Mn, Zn and Si) in the near reservoir and the near little rivers are not in the same degree as those in the rainfall ( some of them are higher than those in the rainfall but others are lower); that nutrient elements content in the rainfall is in the order of K>Zn>Ca>Org N>NH 4 N>NO 3 N>Si>Mg>Mn>P; that the content of P, K, Ca, Mg, Fe, Cu, Mn, Zn and Si in the rainfall inside the stands are all higher than those in the rainfall; that the chemical leaching amount of nutrient elements is up to 79.495 kg·hm -2 a -1 ; that nutrients amount directly entering forestland soil is 161.957 kg·hm -2 a -1 from the rainfall inside the stands, which is the main resource for replenishing the young Chinese fir forestland soil nutrients and exerts an important ecological effect on promoting nutrients cycling and Chinese fir growth; and that of the nutrients amount, Ca is the highest, 73.71 kg·hm -2 a -1 . These results could provide some basic information for sustainable management of the Chinese fir plantation and eco environment protection.