两个地区榄李属植物土壤-茎-叶营养元素及化学计量学特征比较

Study on Soil-Stem-Leaf Nutrients and Stoichiometry Ratio of Lumnitzera Species at Different Areas

以三亚铁炉港红树林保护区和陵水新村港的红榄李(Lumnitzera littore)和榄李(L.racemosa)为研究对象,分析其土壤养分及茎部、叶片营养元素和生态化学计量比,探讨不同地区它们对土壤特性的影响。结果表明:三亚和陵水土壤pH为6.49~8.67,土壤全N和全P含量均较低,但前者N含量高于后者,P含量低于后者;前者速效K含量属富K型(>155 mg/kg),后者速效K含量属适量型(125~155 mg/kg)。红榄李和榄李茎部的N和P含量均低于Ca含量,表明茎部能吸收一定量的Ca能力。三亚地区红榄李和榄李叶片以Ca含量最高,分别为46.07 g/kg和14.98 g/kg;陵水红榄李叶片以Ca含量较高,榄李以N含量较高;但2个地区2个树种叶片N/P均低于14,说明这2个树种主要受N限制。PCA分析结果表明,红榄李和榄李土壤-茎-叶N、P、K等含量之间也均存在显著相关;同一树种在不同地区对土壤、茎部和和叶片因子及化学计量比的响应不同,表明不同地区土壤因子对植物营养元素吸收能力存在差异。

Taking the soil nutrients,stem and leaf nutrients and stoichiometry ratio of Lumnitzera littore and L.racemosa in Sanya Tielugang Mangrove Reserve and Lingshui Xincun Port as research objects,to understand different areas soil properties and effects of two Lumnitzera species.The results showed that the soil pH of Sanya and Lingshui areas were between 6.49 and 8.67,respectively,and the total N and total P contents were lower.However,the N content of former was higher than that of the latter,and the P content was lower than that the latter.Available K content was rich in K type in Sanya(>155 mg/kg),available K content in Lingshui reached K-minimum(125-155 mg/kg).The N and P contents in the stem of L.littore and L.racemosa were lower than Ca content.It indicated that the stem could absorb Ca content.The leaf Ca contents of L.littore and L.racemosa were highest in Sanya,which were 46.07,14.98 g/kg,respectively.The leaf Ca content of L.littore was higher and the N content of L.racemosa was higher in Lingshui.The N/P ratios of different species were lower than 14,which indicated that two species were restricted by N.The results of PCA analysis showed that there were also significant correlations between soil-stem-leaf N,P,K and other contents of L.littore and L.racemosa.The same tree species had different responses to soil,stem,and leaf factors and stoichiometric ratios in different regions,indicating that soil factors had different absorptive capacities for plant nutrients in different regions.