頁籤選單縮合
題名 | 以盆面蒸發量控制臺灣蔗田灌溉之研究=The Effect of Different Pan Ratio for Controlling Irrigation of Sugar Cane in Taiwan |
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作者姓名(中文) | 張灝; 王俊信; 何逢偉; | 書刊名 | 中華農學會報 |
卷期 | 62 民57.06 |
頁次 | 頁1-15 |
關鍵詞 | 盆面蒸發量; 蔗田; 灌溉; |
語文 | 中文(Chinese) |
中文摘要 | (一)據四年期用1.4m3之無底水泥滲漏槽缽值及二年期田間試驗結果,不同盆面蒸發量作為蔗田灌溉標準,?以不同PR(盆面蒸發量)為灌溉標準,在PR0.40, PR0.80, PR1.20 或PR0.50, PR0.75, PR1.00各處理間蔗糖產量差異均不顯著,惟有1965年及1967年三組砂壤土之PR0.40較PR0.80者減產達5%顯著平準;但PR0.80及PR1.20或PR0.75及 PR1.00之蔗糖ˇ產量均高於PR0.40或PR0.50者,此似可顯示PR0.80或可作為臺灣蔗田經濟灌溉之標準。夏威夷試驗結果,PR0.55, PR0.70, PR0.85, PR1.00, PR1.15及PR1.30 各處理間產量差異均未達顯著平準,認為以PR0.85為蔗田經濟灌溉之標準最為合適,此項試驗結果正與本研究之結果完全符合。 (二)6~9月之生長旺盛期內之甘蔗灌溉需水量約佔有全期需水量之60%以上,同期內蔗莖生育期亦佔有全莖高之60~70%,由此可知甘蔗生長最旺盛期亦為需水最多之時期。據回歸分析顯示甘蔗莖高伸長生育量與甘蔗灌溉水量間呈高度的正相關(見圖3),由此可知在臺灣蔗田灌溉為決定甘蔗產量的重要因素。 (三)臺灣以雨量分佈不均,在雨季3~4個月內往往佔有全年降雨量之80%左右,降雨分佈不均而短期內降雨量大者有效雨量降低,降雨量雖少而分佈均勻且短期內降雨量較少者有效雨量率反高(見表7),?有效雨量率與降雨量多少之關係少而與降雨分佈之關係大。據三年來之實測記錄,1964年有三個月之有效雨量超過盆面蒸散量,1965年僅有一個月之有效雨量超過盆面蒸發量,1966年有二個月之有效雨量超過盆面蒸發量,?每年有9~11個月必需行人工灌溉以補足蔗田所需之水分。基於水分平衡之觀點,可知在臺灣蔗田灌溉有如何之重要性;由此亦可知根據盆面蒸發量作為蔗田灌溉之指標與決定灌溉水量之根據實極為重要而合理。 (四)據試驗結果,可知甘蔗需水量依甘蔗產量而異;大體言之,原料甘蔗之需水量約為70~80倍,乾物質之需水量約為200倍左右。每公頃生長良好而可豐產之甘蔗全期約需水1,500~2,200mm(內約有50~60%之水量來自有效雨量)。全期平均約為PR1.00左右,一個月之甘蔗約為PR0.40左右,夏季生長旺盛期約為PR1.3~1.4,灌溉量可以此為標準。 (五)砂土甘蔗產量顯著低於黏壤土及砂壤土可達於1%之差異顯著平準,後二者間差異不顯著。砂土產量低落之主要原因,可能為線蟲病害,如砂土用DBCP等土壤燻蒸劑控制線蟲,再加以充分灌溉與足量施肥,仍可達到豐產之目的。但以砂土保水力較差,可能灌溉需水量略多於黏壤土或砂壤土。 |
英文摘要 | The results from some lysimeter investigations and field experiment in the study indicate that there is no significant difference between the different irrigation treatment with various PR (pan evaporation rate). The highest yield is obtained from PR 0.75 (1964, 1966), PR 0.8 (1965), PR 1.00 (1964) or PR 1.20 (1966) and the lowest yield is obtained from PR 0.5 (1964, 1966, 1967) and PR 0.4 (1965, 1966, 1967). In 1965, and 1967 the difference between PR 0.4 and PR 0.8 in sandy loam soil was significant at the 5% level. These data show that the PR 0.80 may be used as a standard for optimum irrigation in the sugarcane field in Taiwan. Since the potential evapotranspiration of sugarcane is approximately the same as pan evaporation, it is possible to estimate the yield by the water balance technique. In the water balance graphs, the difference between pan evaporation and effective rainfall represents the approximate water deficit of the area. Since the distribution of rainfall is very uneven in Taiwan and there is a difinite relationship between pan evaporation and effective rainfall and consumption use of water of sugarcane in Taiwan, it is clear that the irrigation in this area is very important. The highly significant correlation coefficients between cane stalk elongation and amount of irrigated water indicate that water requirement is an important determinate of yield of cane in this study. Experimental data indicate that the potential evapotranspiration or consumption use of water of one hectare of a good crop of cane is about 1,500~2,200 mm (55~60% of it from effecitive rainfall). Just as 60~70% of the water consumption occure in the four months from June to September, 60~70% of the total length of cane stalks is formed in the same period. The ratio of water requirement to the weight of millable canes and to the dry matter of cane plants are found about 60~80:1 and around 200:1 respectively. The PR is over 1.3~1.4 in summer from June to September and below 1.00 in the spring and average around 1.00 in the course of one year. It is the same as the experimental results in Hawaii. Root-knot nematodes may be the main couse for the very low yield of cane in the sandy soil. The fumigant DBCP were quite effective in controlling the root-knot nematode of sugarcane in the sandy soil. The use of fumigant, optimum irrigation, and full fertilizer may produce optimum yield of cane from sandy soil. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。