水田土壤特性與水稻收量之關係研究

Characteristics of the Slate Alluvial Soils in Central Taiwan Associated with the Growth of Lowland Rice

李予純(T.S. Lee) ； 林家棻(C.F. Lin)

《中華農業研究》 25卷3期 (1976/09) Pp. 183-190

https://doi.org/10.29951/JARC.197609.0002

摘要

爲探討中部粘板岩冲積土性質與水稻生長及產量的關係，62年度在濁水溪灌溉區域內溪州、田尾、西螺及北斗四鄉鎮，各依當地水稻產量高低選取二處，共計八處，包括粘板岩新舊冲積土，分屬六種不同土系，同時進行田間及溫室水稻栽培試驗。結果盆栽試驗與田間相符合，凡田間收量低者，盆栽亦低。就水稻生育期中，每隔兩星期採取土壤溶液測定結果，顯示稻穀收量除與土壤氮、磷、鉀釋放能力有顯著正相關關係以外，並與土壤溶液之PH值，HCO3(上標 -)及Ca(上標 2+)之含量呈顯著負相關關係，而田間結果認爲稻穀收量與土壤排水性能或水分慘透率甚有關係。
爲配合田間試驗，仍以濁水溪粘板岩冲積土在本所溫室舉行盆栽試驗，以探討土壤肥力，排水與否對於稻穀收量之影響。共用土壤36個，分別採自濁水溪流域田間試驗地區，處理分排水與否兩種，排水者水自試驗盆底側所裝之玻璃管排出，每日約1公分。重複兩次，計36×2×2=144盆，依逢機區集法排列於溫室，肥料施用量各盆相同，爲N 80ppm, P及K各50ppm。
本試驗共植水稻二期，一期作自63年2月至8月；二期作自63年8月至64年1月。結果摘要如下：
1．土壤性質與稻穀產量之關係與稻穀產量關係最密切的土壤性質爲土壤的陽離子交換總量(CEC)及有機質(O．M.)，有效磷(Available P)的含量，均與稻穀產量成顯著正相關關係；而土壤的PH及交換性鈣的含量則與稻穀產量有顯著負相關關係。
2．土壤溶液內化學成分含量與稻穀產量之關係稻穀產量與土壤溶液內之PH值，HCO3(上標 -)及Ca(上標 2+)之含量呈顯著負相關關係，與土壤溶液內NH4(上標 +), P, Fe(上標 2+)及有機酸的含量呈顯著正相關關係。有機酸對水稻產量的影響應係其對土壤溶液PH的影響而來。
3．排水對稻穀產量之影響排水對二期作水稻產量影響較大。二期作排水處理較不排水者稻穀平均產量高14.05%，一期作則僅高4.51%。由土壤溶液測定知排水對其中PH值，NH4(上標 +)及P的含量影響不大，但對其他成分含量的影響極大，即排水顯然減少土壤溶液中Total organic acid, HCO3(上標 -)，K(上標 2+)，Mg(上標 2+), Mg(上標 2+)，Fe(上標 2+)及Mn(上標 2+)的含量，且排水對二期作土壤溶液的影響較一期作爲大。
如以排水處理的稻穀產量爲100，求同一土壤不排水處理的產量百分比，則二期作中各土壤不排水處理的稻穀產量百分比仍與土壤溶液中的PH值，HCO3(上標 -)及Ca(上標 2+)的含量成顯著負相關關係。
概言之，本試驗所得結果仍與去年度所作中部粘板岩土壤性質與水稻產量之關係極相符合。即此等土壤之水稻產量除與土壤中的氮、磷釋放能力有極顯著的正相關關係外，並與土壤之pH值，鈣之含量及土壤溶液中HCO(下標 d)(上標 -)含量成顯著負相關關係。排水確能增加水稻產量，但對二期作影響較大，可增產稻穀14.05%；一期作則僅能增產4.51%。

並列摘要

The purpose of this study was to evaluate soil fertility, drainage or not as related to the yield of rice in the slate alluvial soils in central Taiwan. This was actually a continuous study of 1973.
36 soils selected from the Cho Shui irrigation area in central Taiwan were used in this greenhouse experiment. Two treatments, with and without drainage with two replicates, a total of 36×2×=144 pots were arranged in the greenhouse in a randomized complete block design. 1 cm of water per day was drained from the pots of the drainage treatment.
Two crops of rice were planted in this experiment. The first crop was from February to August 1974, and the second, from August 1974 to January 1975. The results was more or less the same as the former experiment in 1973. It was summarized as follows:
1. The relation between rice yield and soil characteristics Soil PH and its calcium content were the most important factors affected the grain yield, both were negatively correlated with yield. While as the cation exchange capacity, organic matter, and available phosphorus content of the soil were positively correlated with grain yield.
2. The relation between rice yield and chemical composition of the soil solution: The PH value, HCO3(superscript -), and Ca(superscript 2+) content in the soil solution were correlated negatively with the yield of grain. While as the amount of NH4(superscript +), P, Fe(superscript 2+) and total. organic acid in the soil solution were correlated positively with rice yield. (the significant correlation between total organic acid and rice yield was actually due to the effect of total organic acid on the PH of the soil solution).
3. Effect of drainage on rice yield Drainage indeed increased the yield of rice. The effect was more significant in the second than the first crop. Drainage increased the yield of grain by 14.05% and 4.51% in the second and first crop respectively.