臺灣博碩士論文加值系統

植物葉部養分對植物的活力與生產力具有重要的影響，季節的變化與地形的差異造就了植物葉部養分在時間上與空間上的變異，因此是植物生理生態學上重要且值得探討的主題。本研究以福山試驗林第一集水區的11種植物為調查對象，研究植物葉部養分濃度受季節變化與地形的影響，並採集三個地形的土壤以了解土壤特性與植物養分間的關係。自2005年4月至2005年11月，共採集植物樣本4次及土壤樣本1次以進行葉部養分及土壤性質分析。結果顯示，受到地形的影響，福山土壤養分肥力狀況與植物葉部養分地位皆可分為「溪谷型」與「中坡─稜線型」兩大類。溪谷型土壤的pH、土壤有效性磷、可交換性陽離子鈣、鎂與土壤鹽基飽和度顯著高於中坡─稜線型土壤(P ≦ 0.0087)。溪谷植物葉部巨量元素(氮、磷、鉀、鈣、鎂)養分濃度顯著高於中坡─稜線植物(P < 0.0001)，可能是反應溪谷土壤肥力較高的結果。在季節變化方(依據植物不同生理年齡，4月新葉〜11月老葉)面，植物葉部氮、磷、鉀的濃度會隨著季節變化而減少，鈣、錳的濃度則會隨著季節變化而增加，鎂的濃度季節變化則較不一致，隨植物種類不同而異。在養分再吸收效率的表現上，磷(58.3%)、鉀(48.1%)的再吸收效率顯著高於氮(23.7%)的再吸收效率(P = 0.0001)；中坡─稜線植物磷(64.1%)、鉀(55.4%)的再吸收效率顯著高於溪谷植物磷(41.1%)、鉀(26.1%)的再吸收效率(P ≦ 0.0047)，而氮的再吸收效率在兩地形則無顯著差異。中坡─稜線植物葉部具有較高的養分再吸收效率(例如：PRE)，可能是為了適應土壤肥力較低環境所形成的因應策略。在11月時兩類地形之植物葉部氮濃度皆很高，顯示氮尚未再吸收完全；在11月時溪谷的磷濃度也很高，顯示磷也尚未再吸收完全，相對地，中坡─稜線植物磷濃度則接近再吸收作用的臨界值，顯示在土壤肥力較低的環境磷再吸收作用較完全。

Foliar nutrition can influence vigor and productivity of plants. The seasonal changes and topographical difference cause the temporal and spatial variations in foliar nutrient composition. Both are important topics and worth further discussion in plant ecophysiology. In this study, I collected leaf samples from 11 plant species and soil samples to investigate the effects of seasonal change and topographical difference on foliage nutrient compositions in Watershed #1, Fushan Experimental Forest. I collected leaf samples four times and soil samples once from April to November, 2005. The results showed that soil fertility and nutrient concentrations in foliage could be classified into “bottom type” and “middle-top type”. Bottom type soil had significantly higher pH, available phosphorous, exchangeable calcium, exchangeable magnesium, and base saturation than middle-top type soil (P ≦ 0.0087). The foliar concentrations of nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), were significantly higher in bottom type plants than in middle-top type plants (P < 0.0001). The differences in the foliar nutrient compositions could be a response to the differences in soil fertility between bottom type and middle-top type. In eight out of eleven species, the foliar concentrations of N, P and K increased with sampling sequence, but those of Ca and manganese (Mn) decreased. Seasonal patterns of foliar Mg concentrations were inconsistent and dependent on plant species. In nutrient resorption efficiency (RE), P (58.3%) and K (48.1%) resorption efficiency (PRE, KRE) were significantly higher than N (23.7%) resorption efficiency (NRE) (P = 0.0001). Middle-top type plants had significantly higher PRE (64.1%) and KRE (55.4%) than bottom type plants (P ≦ 0.0047), whereas there was no significant difference in NRE between bottom type and middle-top type plants. The high resorption efficiency might be a strategy of plants to adapt to low soil fertility. In November the foliar N concentrations were still rather high in plants of both types, suggesting the incomplete resorption. In November, similarly, the high concentrations of foliar P in bottom type plants also suggested the incomplete resorption. By contrast, the foliar P concentrations in middle-top type plants had approached the threshold of resorption proficiency in November, indicating the more complete P resoprtion in the soil with low fertility.

目錄
中文摘要…………………………………………………………………….……I
英文摘要………………………………………………………………...……….II
圖目錄…………………………………………………………………………..VI
表目錄………………………………………………………………....……….VII
附錄目錄………………………………………………………………………..IX

前言 ……………………………………………………………………………..1
前人研究…………………………………………………………………………3
一. 地形對土壤的影響…………………………………………………...3
二. 土壤與植物的交互作用……………………………………………...4
三. 植物葉部養分濃度的變異…………………………………………...6
四. 植物養分再吸收作用………………………………………………...7
材料與方法……………………………………………………………………..11
一. 研究區概述………………………………………………………….11
二. 樣本採集…………………………………………………………….13
三. 實驗室分析………………………………………………………….15
四. 資料分析…………………………………………………………….18
結果……………………………………………………………………………..21
一. 土壤性質……………………………..……………..……………….21
二. 植物種類間葉部養分濃度的比較..……………..………………….25
三. 葉部養分的季節變化與地形間的差異…………………………….26
四. 植物養分與土壤性質之相關……………………………………….30
五. 養分再吸收效率…………………………………………………….32
討論……………………………………………………………………………..33
一. 地形對土壤的影響………………………………………………….33
二. 地形對植物養分濃度的影響……………………………………….34
三. 植物種類對養分濃度的影響……………………………………….36
四. 季節變化對葉部養分濃度的影響………………………………….38
五. 植物的養分再吸收作用…………………………………………….40
結論……………………………………………………………………………..46
參考文獻………………………………………………………………………..49
附錄……………………………………………………………………………103
圖目錄
圖1a、 福山試驗林第一集水區位置圖 (引自夏禹九等，1996)………………................58
圖1b、 福山試驗林第一集水區25m等高線地形圖…………………...............................58
圖2a、 11種植物葉部養分濃度的分佈(n = 531)………………………………………....59
圖2b、 11種植物葉部養分濃度的對數分佈(n = 531)………………………………........60
圖3、 長梗紫苧麻葉部養分濃度在不同月份之變化…………………………………....61
圖4、 台灣雅楠葉部養分濃度在不同月份之變化………………………………………62
圖5、 廣葉鋸齒雙蓋蕨葉部養分濃度在不同月份之變化………………………………63
圖6、 山龍眼葉部養分濃度在不同月份之變化…………………………………………64
圖7、 長葉木薑子葉部養分濃度在不同月份之變化……………………………………65
圖8、 烏皮茶葉部養分濃度在不同月份之變化…………………………………………66
圖9、 鋸葉長尾栲葉部養分濃度在不同月份之變化……………………………………67
圖10、 紅楠葉部養分濃度在不同月份之變化……………………………………………68
圖11、 黃杞葉部養分濃度在不同月份之變化……………………………………………69
圖12、 綠樟葉部養分濃度在不同月份之變化…………………………………………....70
圖13、 三斗石櫟葉部濃度元素在不同月份之變化………………………………………71

表目錄
表1、 研究樣區的基本資料………………………………………………………………72
表2、 不同地形與土壤深度之土壤性質…………………………………………………73
表3a、 腐植質層各土壤屬性間之相關分析 (n = 9)……………………………………...75
表3b、 土壤深度0〜10 cm的各屬性間之相關分析 (n = 9) ……………………………76
表3c、 土壤深度10〜20 cm的各屬性間之相關分析 (n = 9)… ………………………..77
表3d、 土壤深度20〜30 cm的各屬性間之相關分析 (n = 9) …………………………..78
表4、 11種植物葉部各養分平均濃度 (n = 531)…………………………………......…79
表5、 11種植物經logarithm轉換後葉部各養分平均濃度之分級(n = 531)…………..80
表6、 三種地形之植物葉部養分平均濃度 (n = 531)…………………………………...81
表7、 長梗紫苧麻在不同月份間葉部各養分之濃度…………………………………....82
表8、 台灣雅楠在不同月份間平均葉部養分濃度…………………………………..…..82
表9、 廣葉鋸齒雙蓋蕨在不同地形間與月份間平均葉部養分濃度……………………83
表10、 山龍眼在不同地形間與月份間平均葉部養分濃度………………………………84
表11、 長葉木薑子在不同地形間與月份間平均葉部養分濃度…………………………85
表12、 烏皮茶在不同地形間與月份間平均葉部養分濃度………………………………86
表13、 鋸葉長尾栲在不同地形間與月份間平均葉部養分濃度…………………………87
表14、 紅楠在不同地形間與月份間平均葉部養分濃度…………………………………88
表15、 黃杞在不同地形間與月份間平均葉部養分濃度…………………………………89
表16、 綠樟在不同月份間平均葉部養分濃度……………………………………………90
表17、 三斗石櫟在不同月份間平均葉部養分濃度………………………………………91
表18a、植物葉部養分濃度與腐植質層各土壤屬性之相關分析 (n = 531)………….......92
表18b、植物葉部養分濃度與土壤深度0〜10 cm各屬性之相關分析 (n = 531)……….92
表18c、植物葉部養分濃度與土壤深度10〜20 cm各屬性之相關分析 (n = 531)……...93
表18d、植物葉部養分濃度與土壤深度20〜30 cm各屬性之相關分析 (n = 531)……...93
表19a、廣葉鋸齒雙蓋蕨葉部養分濃度與腐植質層各土壤屬性之相關分析 (n = 81).....94
表19b、廣葉鋸齒雙蓋蕨葉部養分濃度與土壤深度0〜10 cm各屬性之相關分析 (n = 81)………………………………………………………………………………….95
表19c、廣葉鋸齒雙蓋蕨葉部養分濃度與土壤深度10〜20 cm各屬性之相關分析(n = 81)………………………………………………………………………………….96
表19d、廣葉鋸齒雙蓋蕨葉部養分濃度與土壤深度20〜30 cm各屬性之相關分析(n = 81)………………………………………………………………………………….97
表20a、山龍眼蕨葉部養分濃度與腐植質層各土壤屬性之相關分析 (n = 81)…………..98
表20b、山龍眼葉部養分濃度與土壤深度0〜10 cm各屬性之相關分析 (n = 81)………99
表20c、山龍眼葉部養分濃度與土壤深度10〜20 cm各屬性之相關分析 (n = 81)……100
表20d、山龍眼葉部養分濃度與土壤深度20〜30 cm各屬性之相關分析 (n = 81)……101
表21、 主要樹種之養分再吸收效率……………………………………………………...102
表22、 溪谷型植物與中坡─稜線型植物之養分再吸收效率……………………………102

附錄目錄
附錄 1、 三種地形在不同土壤深度之土壤性質…………………………….….....103
附錄 2、 11種植物4月新葉(Apr29)各養分平均濃度(n =174)…………….……..105
附錄 3、 7種植物6月(Jun06)各養分平均濃度 (n =95)…………….....................106
附錄 4、 11種植物8月(Aug11)各養分平均濃度 (n =178)……………………....107
附錄 5、 11種植物11月(Nov06)各養分平均濃度 (n =179)…………………......108
附錄 6、 7種植物4月老葉(Old Apr29)各養分平均濃度 (n =93)…………….….109

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