頁籤選單縮合
題名 | 紅棕壤之主要營養素受水稻連續栽培影響的研究=The Major Nutriends of the Reddish Brown Latosol as Influenced by Continuous Rice Croppings |
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作 者 | 陳振鐸; 魏金塗; | 書刊名 | 中華農學會報 |
卷期 | 34 民50.06 |
頁次 | 頁9-17 |
關鍵詞 | 紅棕壤; 水稻; 連續栽培; 營養素; |
語文 | 中文(Chinese) |
中文摘要 | 紅棕壤之肥力概低,而氮、磷、鉀肥之肥效均大。為明瞭此特性,作者等曾於1952~1958年間,使用WAGNER 盆栽行第一及第二作水稻之三要素試驗。同時,分析經栽培後一年與連續栽培二、三、四年後之紅棕壤(平鎮粘土),以檢定各種型態氮、磷、鉀含量在各期內之變化。在本試驗中,以沖積土(臺北系坋砂壤土)行同樣試驗,以資比較,試驗結果如下: (一)紅棕壤較於沖積土,常迅速的消耗無肥區及無氮區之可利用性或可礦物化性氮(由C/N及活性指數認定之),但兩種土壤全氮損失量之差異為不顯著。 (二)紅棕壤原含的各種形態磷,較於沖積土者為少。其無肥與無磷區較迅速的消耗全磷。不活性磷、NH4F可溶性磷等。 (三)紅棕壤原含的全鉀、置換性鉀、1NHNO3可溶解鉀較於沖積土者為少。其無肥與無鉀區較迅速的消耗置換性鉀。 (四)紅棕壤之貯藏三要素量較低,加之其可利用態者之消耗迅速,此?為氮、磷、鉀三要素肥料的肥效,在該土壤均為顯著之理由。 |
英文摘要 | It is generally known that the reddish brown latosol of Taiwan (4) is very low in fertility. However, the information regarding the depression rate of major nutrients in various forms, as a result of continuous rice croppings, and the explanation of the high response of N, P and K to this soil is rare. Therefore, an attempt was made to investigate on the distribution of major nutrients in the latosol, and their depression rate brought by continuous croppings, so as to explain the high response of N, P and K fertilizers in this soil. This investigation was made through the continuous rice croppings under various fertilizer treatments for four years, and analyzing the soils. Moreover, the changes in the distribution of nutrients of the latosol were compared with those of the alluvial soil. The results of experiment may be summarized as follows: (1) The pH, nitrogen and organic matter of variously treated soils after continuous croppings are shown in table 1. It was observed that the pH was affected by the treatment remarkably. The pH of N and no K plots were high in both soils, and the change in pH of the fertilized plots was generally less than that of unfertilized plots throughout the croppings. (2) The rate of decrease of nitrogen and organic matter through continuous cropping was particularly significant in no N and unfertilized plots in both soils, and the latosol showed lesser rate of decrease than that of the alluvial soil. An investigation was also made on the C/N and activity index (5) of variously treated field soils of the latosol and the alluvial. The results are shown in table 2. It may be known from the table that there was a gradual release of nitrogen from the H2O residue to H2SO4 residue in the alluvial soil. However, under the same treatment, the release, of nitrogen was less in the latosol. This indicates that the organic combination of N of latosol was stronger than that of the alluvial soil. The same table also shows that the change in the lignin content or the manifestation in activity index (I2 consumption in m. e. per gram of carbon) (5) was slightly less in the latosol. These indicate the latosol contained the higher percentage of less decomposable organic materials. These data may explain the rapid available N depression of the latosol, and the reason why its rate of decrease of total N after continuous croppings was less than the alluvial soil and also high response of N fertilizer to this soil. (3) The changes in the content of various forms of phosphorus after continous croppings are shown in table 3 and fig. 1. It may be noted that there were striking changes in total P, total P, inorganic acid soluble P, inorganic alkali soluble P and NH4F soluble P among various plots, and their decreases were particularly significant in unfertilized and no P plots of the alluvial soil. While in the latosol, there was only significant decreases of total P, inert P and NH4F soluble in the same two plots. The rate of decrease of total P in no P and unfertilized plots of the latosol were 41.3% and 47.8% respectively after 3 croppings. On the other hand, the alluvial soil showed lower rate of decrease in total P and inert P after 3 croppings. The rate of decrease of total P in no P and unfertilized plots were 15.6% and 20.9% respectively, and that of inert P in the two plots were 14.6% and 21.7% respectively. The depletion of total P of the paddy latosol after continuous cropping were particularly rapid comparing to other form P and those of the alluvial soil. The rapid depression of total P and inert P (decrease in storage capacity of available P) may be a main reason why latosol shows a high response to P fertilizer. (4) The result of K analysis is shown in table 4, 5 and fig.2. These revealed that the decrease of total K in various treatment plots of both soils after continuous croppings was not significant. This did not conform with the total P of previous statement, which decreased remarkably. However, the decrease of exchangeable K in both soils of no K and unfertilized plots was significant. The alluvial soil decreased 52.0% and 45.8% exchangeable K in no K no fertilizer plots respectively, and the latosol decreased 57.6% in no K plots. The degree of exchangeable K saturation of the two original soils and after 3 years croppings were shown it table 4. It may be observed that the change in the degree of K saturation in latosol was greater than in the alluvial soil. The lower exchange capacity and higher bonding energy of K halloysite (the principal clay mineral of the Pinchen series) than that of illite (the principal clay mineral of the Taipei series) would bear a close relation to this finding (8). There was no significant relation between the continuous croppings and 1 N HNO3 soluble K for the Taipei series however, no K plots showed the lower content of 1 N HNO3 soluble K. From this experiment, the high response of latosol to K fertilizer may be explained by its low content of total K, the small exchange capacity, and the higher saturation percentage of exchangeable K. (5) The early and late rice yield of each treatment plot of the latosol and alluvial soil after continuous croppings for 1-3 years are shown in fig. 3. It may be known from these data that: (a) The rate of decrease in yield of no P and no K plots were smaller than that of no N plot in the first year crop, but in the later years their decrease rates were as large as those of no N plots in both soils. (b) The yield reduction of latosol was much greater than that of alluvial soil after 1st cropping. The rapid decline of no N, no P and no K plots of latosol under flooding condition comparing to that of the alluvial soil may be explained by the results of soil analyses in this investigation as follows: (a) The rapid depletion of small storage of available or easily mineralizable nitrogen from latosol. (b) The rapid exhaustion of small storage of total P, inert P and NH4F soluble P from latosol. (c) The rapid exhaustion of small storage of exchangeable K from latosol. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。