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对天津八仙山国家级自然保护区3种典型阔叶林,即栓皮栎(Quercus variabilis)林、核桃楸(Juglans mandshurica)林、槲栎(Quercus aliena)林凋落物的未分解层、半分解层及下层土壤的养分进行分析,结果表明:(1)在凋落物的未分解层,C含量槲栎林最高为486.1 g·kg-1,栓皮栎林最低为447.5 g·kg-1。N、P含量核桃楸林均最高,分别为17.9和1.2 g·kg-1,槲栎林最低为13.2和0.8 g·kg-1;半分解层,C、P含量三者差异不显著,N含量以槲栎林最高为17.1 g·kg-1,栓皮栎林最低为10.5 g·kg-1。土壤C、N、P含量差异显著(P<0.05),均表现出槲栎林最高,栓皮栎林最低。表明槲栎林自肥能力较强,土壤养分状况良好。(2)C/N、C/P值,在凋落物未分解层中,核桃楸林均小于栓皮栎林和槲栎林,而在半分解层中,3种林分无明显差异;从未分解层到半分解层,栓皮栎林的C/N、C/P值分别下降了17%和11%,槲栎林分别下降了19%和35%,而核桃楸林无明显变化。(3)矿质营养元素含量在凋落物未分解层中按照核桃楸林、栓皮栎林、槲栎林的顺序递减,矿质营养元素含量越大其pH值越接近中性;各林分凋落物矿质营养元素积累总量顺序为:栓皮栎林>槲栎林>核桃楸林。
Three typical broad-leaved forests in the Baxianshan National Nature Reserve in Tianjin, namely Quercus variabilis forest, Juglans mandshurica forest, Quercus aliena forest litter undecomposed layer, semi-decomposed layer The results showed that: (1) In the undecomposed layer of litter, the highest content of C in Quercus alienae was 486.1 g · kg-1 and the lowest in Quercus variabilis was 447.5 g · kg-1. The contents of N and P in Juglans manshurica forest were the highest, which were 17.9 and 1.2 g · kg-1, while the lowest in Quercus alienae was 13.2 and 0.8 g · kg-1. The differences of semi-decomposed layer and C and P were not significant. N The highest content of Quercus liaotungensis was 17.1 g · kg-1 and the lowest in Quercus variabilis forest was 10.5 g · kg-1. The contents of C, N and P in soil were significantly different (P <0.05), which showed the highest in Quercus aliena and the lowest in Quercus variabilis. The results showed that Quercus acutissima was stronger in self-fertilization and had good soil nutrient status. (2) C / N and C / P values. In the non-decomposed layer of litter, Juglans manshurica forest was smaller than Quercus variabilis forest and Quercus aliena forest, while in the semi-decomposed layer, there was no significant difference among the three stands; never C / N and C / P values decreased by 17% and 11% in the cork oak forest, and by 19% and 35% in the deciduous forest to the semi-decomposed layer, respectively. (3) The content of mineral nutrient elements decreased in the sequence of walnut trees, Quercus variabilis forest and Quercus variabilis forest in the litter layer, and the more the content of mineral nutrients was, the closer the pH value was to neutrality. The litter mineral The order of accumulation of nutrient elements was as follows: Quercus variabilis forest> Quercus aliena forest> Juglans mandshurica forest.