Please use this identifier to cite or link to this item:
Effects of Carbon Dioxide and Nitrogen on the Growth and Physiological Responsed of Cinnamomum camphor Seedlings
|關鍵字:||二氧化碳;carbon dioxide;氮肥;樟樹;硝酸還原酵素;硝酸態氮;銨態氮;nitrogen;Cinnamomum camphor;nitrate reductase;NO3--N;NH4+ -N||出版社:||森林學系||摘要:||
本研究係探討樟樹苗木在不同二氧化碳濃度與氮肥處理下之生長與生理反應。樟樹苗木生長於開放式玻璃生長箱中，分別施以350 ±20 μL/L和700 ±30 μL/L二氧化碳濃度以及氮肥(112、224、448與896 ppm)等計8種處理，栽植12週期間，分別從事各項生長測定。
在形質生長表現方面，樟樹苗木處理至後期，於350 μL/L之大氣二氧化碳濃度下，氮肥濃度為448 ppm處理者較佳，而施加氮肥為896 ppm者，生長呈現抑制。然而在提高二氧化碳濃度下，以最高氮肥濃度896 ppm者生長最好。顯然苗木生長在提高二氧化碳濃度下，需要供給較多量的氮肥，才不致於影響苗木的生長。生長於高二氧化碳濃度下，苗木之葉數、總葉面積及各部位乾物量會增加，並且隨著氮肥濃度越高，增加的比例越顯著。
在光合作用方面，於350 μL/L之二氧化碳濃度測定下，生長在大氣二氧化碳濃度之苗木，以高氮肥濃度448及896 ppm處理者高於氮肥濃度之112及224 ppm者；提高二氧化碳濃度下，以氮肥濃度為896 ppm處理者，光合作用的速率最高。氮肥濃度處理若低於448 ppm，光合作用速率以生長於大氣二氧化碳濃度處理者較提高二氧化碳濃度者為高，顯然提高二氧化碳濃度，需供應較高之氮肥，光合作用速率才會提升。葉部及根部之硝酸還原酵素的活性皆隨著氮肥濃度的增加而增加。同一氮肥濃度處理者，提高二氧化碳濃度會使葉部之硝酸還原酵素活性減低，而根部的活性則高於大氣二氧化碳濃度下生長者。由NO3--N濃度與硝酸還原酵素活性互為消長的關係，可得知NO3--N在樟樹苗木之含量多寡受硝酸還原酵素活性之影響。
The objectives of this study were to investigate the effects of elevated carbon dioxide concentration and different nitrogen treatment on growth and physiological phenomena of seedlings in Cinnamomum camphora. Seedlings grown in open-top chambers, were treated with two different carbon dioxide concentrations (350 ±20 μL/L, 700 ±30 μL/L) and four nitrogen concentrations (112、224、448 and 896 ppm) for twelve weeks to measure the growth of height and diameter.
Net height and diameter growth of seedlings was highest in ambient carbon dioxide, 350 ±20 μL/L, wiith the treatment of 448 ppm nitrogen, on the other hand, the growth of height and diameter was restrained wiith the treatment of 896 ppm nitrogen. However, net height and diameter growth was increased in elevated carbon dioxide, 700 ±30 μL/L, with the treatment of 896 ppm nitrogen. Apparently, it needed to supply optimum nitrogen to seedlings when they grew in elevated carbon dioxide. The leaves, total leaf area, and dry matter of seedlings were increased when they were exposed in elevated carbon dioxide
In photosynthesis, when measured at 350 μL/L carbon dioxide, ambient carbon dioxide, the photosynthesis rates of seedlings treated with higher nitrogen concentration(448 and 896 ppm) were higher than with 112 and 224 ppm nitrogen treatment. Seedlings under elevated carbon dioxide their photosynthesis rates were highest in 896 ppm nitrogen treatment. However, when seedlings grew in lower nitrogen(lower than 448 ppm), the photosysthesis rates were not increased in elevated carbon dioxide. Similarly, the higher the nitrogen concentration, the more significant in increment. Nitrate reductase activity of leave and roots were significantly increased by higher nitrogen treatment. Compared with in ambient carbon dioxide, nitrate reductase activities of leave were declined in elevated carbon dioxide under the same nitrogen treatment. Nitrate reductase activities of roots were higher in elevated carbon dioxide than in ambient condition. The relationship between NO3--N concentration and nitrate reductase activity showed that NO3--N concentration in seedlings of Cinnamomum camphora were influenced by nitrate reductase activity.
|Appears in Collections:||森林學系|
Show full item record
TAIR Related Article
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.