頁籤選單縮合
題 名 | 茶園相思樹遮蔭對茶樹生長之影響的研究 |
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作 者 | 吳振鐸; | 書刊名 | 中華農學會報 |
卷 期 | 75 1971.09[民60.09] |
頁 次 | 頁1-34 |
關鍵詞 | 生長; 相思樹; 茶園; 茶樹; 遮蔭; |
語 文 | 中文(Chinese) |
中文摘要 | 相思樹(Acacia condusa Merr)為本省茶園最普遍作防風及遮蔭之用的一種常綠樹木,但種植後,對茶樹之生長及生葉收量等有何影響,國內外過去尚未有較正確的試驗報導,作者自民國43年(1954)開始利用本場後山32%的坡地作平臺卵石階段分全遮蔭(Full Shade) "A" 區半遮蔭(Partial Shade) "B" 區及無遮蔭(Without shade) "C" 區三處理,每小區面積89.60平方公尺(14×6.4),共重複8次,田間為逢機完全區集設計(Rankdomized complete block design)試驗開始時先種植魯冰綠肥作空白試驗以測定其地力。相思樹苗較茶苗早二個月定值,茶苗用青心大有種,於44年1月底定植,定植後相思樹生長較為迅速至第3年已高達4公尺餘,開始收遮蔭之效,茶樹至5年生為幼木期,6-10年生為成木期11年(1965)生時離地面12公分處行深剪枝,12至15年生為深剪枝更新成木期,此三時期中每年各處理之生長量及生葉收量均予詳為統計分析,同時於成木期中測定各小區土壤中及生葉中主要化學成份的含量,探討其受相思樹遮蔭的影響,本年並測定各小區之日照光度及採摘面與採摘面下20公分處之溫度,茲將本試驗結果分別摘要於後: (一)經種植魯冰綠肥測定的結果,各區集間的地力雖有差別,但三處理間的地力,經新多種變域測定的結果,並無明顯的差異,該試驗區甚適於舉行試驗之用。 (二)茶苗定植後的成活率最低的區集(77.2%)與最高的區集(96.8%)之間雖有顯著的差別,但不同遮蔭度三處裡間的差異並不明顯,總平均"C"區為90.6%與"B"區之90.4%極相近,而"A"區亦僅低3.3% (87.3%) 並未達0.05的顯著基準。 (三)相思樹遮蔭對茶園土壤化學性質的影響:據本場試驗定植後10年採取土壤分析的結果,相思樹遮蔭確可提高茶園土壤中有效性磷的含量,有效性含量"A"區為21.29 ppm "B"區為15.37 ppm 而"C" 區只9.25 ppm,相思樹遮蔭對土壤中有效性鉀,全氮量以及pH值,並無明顯的影響。 (四)相思樹遮蔭對茶樹生長量的影響:茶園幼木期中種植相思樹行輕度的遮蔭(Light Shading)有利於幼木茶樹的生長。 茶樹成木後達8年生時,不論全蔭"A"區或半蔭"B"區的生長量確較無蔭"C"區為低,尤以氣候乾旱的差異更為顯著,茶樹深剪更新後的生長量,亦以無蔭"C"區較全蔭"A"區或半蔭"B"區為大,總之,在本試驗環境條件下成木茶園不論相思樹遮蔭度之大小,均影響茶樹的生長,尤其相思樹達8年生後的影響更為顯著。 (五)相思樹遮蔭對茶樹生葉收量的影響:茶樹幼木期中,幼木相思樹輕度遮蔭時,半蔭"B"區的生葉收量較無蔭"C"區增加26%,全蔭"A"區亦比"C"區增加12%其差異亦達0.05的顯著基準。 茶樹成木期中的收量,據本試驗6至10年生的平均統計,遮蔭處理間的差異極為顯著,全蔭"A"區的收量只及無蔭"C"區的63.94%,半蔭"B"區的75.86%而"B"區亦只達"C"區的84.29%。無蔭"C"區的茶樹達10年生時生葉甚壯旺,生葉收量亦高,但全蔭或半蔭區茶樹7年生時已甚衰弱,7年生後的生產量?急速下降,至10年生時半蔭"B"區的收量只及無蔭"C"區的50%,全蔭"A"區只及"C"區的23.6%,"A"區已只及半蔭"B"區的46.8%。 深剪更新後遮蔭區的生產力亦難以恢復,據深剪後4年的平均,全蔭"A"區的收量只無蔭"C"區的35%,半蔭"B"的65%,"A"區亦只及"B"區的52.8%,差異極為顯著。 據本試驗的結果,很明顯的指出本省小葉種茶樹區若密植相思樹達7年生以上尚未砍伐者,其茶樹立?衰弱,生產力急趨下降,必須立即砍伐相思樹,並剪枝更新茶樹才能逐漸恢復生產力,若十年後砍伐更新,極難以恢復了。 (六)據本試驗茶樹生葉收量及生長量的統計分析,作者建議,本省開闢小葉茶園若種植相思樹防風遮蔭其種植距離以行距13.0至19.0公尺,株距2.0至6.0公尺較為適宜,且必須行7年間伐輪植制,才能保持其優越的生產力。 (七)相思樹遮蔭對茶葉中化學成分的影響,據本試驗分析第二嫩葉及老葉中的全N量,有效性磷、鉀、鈣及鎂的結果,相思樹遮蔭與否,對茶葉中氮磷及鉀的含量並無明顯的影響,嫩葉普遍較老葉為高。但鈣的含量隨遮蔭度之增加而顯著的減少,尤以老葉中所含著為甚,而鎂的含量,適得其反,隨遮蔭度之增加而增加,全蔭"A"區(0.61%)較無蔭"C"區(0.21%)增加三倍,而半蔭"B"區亦增加79.4%。葉中鎂含量的提高,將可改進其品質,此容於另一專題中報導之。 (八)相思樹遮蔭對茶樹葉溫的影響,據本試驗區本夏測定的結果,採摘面無蔭"C"區平均的溫度(34.9℃)確較"B"區(33℃)及"A"區(30.4℃)為高,採摘面下20公分處的溫度"C"區(32.5℃)亦確較"B"區(31.4℃)及"A"區(30.1℃)為高,可見小葉種採摘面溫度平均達34.9℃並不影響其正常的生長。 |
英文摘要 | Acacia confusa is widely used for the purpose of windbreak and shading effect in the tea plantation of Taiwan. A field experiment was conducted on a 32% sloped land, about 200-222 meters above see level and reddish yellow colored Diluvial soil and was located near the Station. The experiment was laid out in a randomized complete block design and each treatment had eight replicated. The treatments of the different plots are shown in the table. The plot was 14.0×6.4 meters in size. The most popular Chinese tea variety in Taiwan, Chin-shin Dah-pang, Camellia sinensis var, sinensis was used in this study. Planting of tea bushes was done in Jan. 1955 and seedling of the shade tree were planted two months earlier, the growth of the shade tree was more rapid than that of the young tea. After three years, the shade trees had grown to a height over three meters and began their shading function. All of the experiment plots received same manuring, pruning, and other cultures. Heavy pruning of both tea bushes and shade trees was carried out in 1965 when they were eleven years old. The main object of this experiment was to investigate the effect of shade trees on the growth rate and yield of tea bushes. The chemical property of the soils, the chemical composition of tea leaves and the temperature were also studied. Ther results of the experiment may be summarized as follows: 1. Effect on the soil properties-- An analysis of total N.,pH value and contents of available P.K. and Ca. of soil samples taken ten years after starting the expt. showed that available P. was significantly increase with shade trees over that with full sun. No significant differences were found between other treatments. 2.Effect on the growth rate of tea bushes-- In young tea bushes less than five years old, the two shading treatments gave quicker growth, but when the tea bushes reached eight to fifteen years old, an opposite result was obtained that growth was more rapid without shade than with shade. 3. Effect on the yield of tea-- The yield of tea from different treatments during the period from 1954to 1969 was shown in the following table:-- If was clear from the table that a benefical effect on the yield of tea leaves was obtained by partial shade provided to young tea bushes. In the mature stage, however, the yield was the highest in the plots with no shading. Similar result was obtained after heavy pruning. It was also indicated from the experiment that the shade tree should never be allowed to become too large, it must be removed from roots before seven years old under the climatic conditions of Taiwan. 4. Effect on the chemical compositions of tea leaves-- It was found that the concentrations in tea leaves of N.P. and K. were not significantly different between the treatments. The content of available Mg. was increased as the degree of shading increased. But with the available Ca., the opposite result was obtained. 5. Effect on the temperature-- Temperature at the plucking surface or in a depth of 20 cm from the surface was found to be 4.9℃ or 2.4℃ higher in the fullsun plots than the shaded plots. This result indicated that although an average temperature of 34.9℃ at the plucking surface of tea bush as observed in the unshaded plots produced no adverse effect on the normal growing of the Chinese variety of tea plamt. |
本系統中英文摘要資訊取自各篇刊載內容。