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本文研究了氮、磷、钾、钙和镁5个养分元素在广东西江地区杉木人工林不同立地不同龄组的含量和分配。结果表明这些养分元素在杉木林分的含量与立地条件的好坏和林龄的大小显著相关,Ⅲ立地1、2和3龄组林分的养分元素总贮量分别为23.2、34.8和67.0公斤/亩;Ⅱ立地1—3龄组分别为47.3、52.8和91.1公斤/亩;Ⅰ立地1—3龄组分别为50.6、62.6和125.7公斤/亩。各器官生物量和养分元素含量分配不均匀,干材生物量约占树体总生物量的一半以上,但养分含量却很低;树冠(枝、叶、花和果)的生物量约占总生物量的20％,而养分含量约占养分总量的50％以上;叶子生物量低,但氮素含量高,如Ⅱ立地1龄组的叶子生物量仅占总生物量11.4％,氮素含量却占总氮量的64.8％。各器官的养分含量依次为叶>花果>枝条>树根>树干。不同立地不同龄组的林分养分元素含量,Ⅰ、Ⅱ立地之间无显著差异,而它们与Ⅲ立地则有显著差异;2、3龄组之间无显著差异,而它们与1龄组有显著差异;钙的含量3龄组显著地高于1、2龄组;氮、磷、钾在叶子和根系的含量1龄组的显著地高于2、3龄组的。
In this paper, the content and distribution of nitrogen, phosphorus, potassium, calcium and magnesium in five different sites of Cunninghamia lanceolata plantation in the Xijiang area of Guangdong Province were studied. The results showed that the contents of these nutrient elements in the Chinese fir plantation were significantly correlated with the site conditions and the stand age. The total nutrient contents of the stand 1, 2 and 3 in the stand Ⅲ were 23.2, 34.8 and 67.0 kg / Acre; Ⅱ site 1-3 age group were 47.3,52.8 and 91.1 kg / acre; Ⅰ site 1-3 age group were 50.6,62.6 and 125.7 kg / acre. The organs biomass and nutrient elements were unevenly distributed. The dry biomass accounted for more than half of the total biomass of the tree, but the nutrient content was very low. The biomass of crown (branches, leaves, flowers and fruit) Biomass of 20%, while the nutrient content of about more than 50% of the total nutrients; leaf biomass is low, but the nitrogen content is high, such as Ⅱ stand the first group of leaf biomass accounted for only 11.4% of the total biomass, nitrogen But the content of total nitrogen 64.8%. The nutrient contents of various organs were leaves> flower fruit> branches> roots> tree trunk. There were no significant differences in the nutrient elements content of stands in different sites and age groups, but there were significant differences between sites Ⅲ and Ⅱ. There was no significant difference between the two groups The content of calcium in the 3rd instar was significantly higher than that in the 1st and 2nd instar. The content of nitrogen, phosphorus and potassium in the leaves and roots of the 1st instar was significantly higher than that of the 2nd and 3rd groups.