Please use this identifier to cite or link to this item:
|標題:||The effects of soil moisture and temperature regimes on the transportation of potassium forms in the soils
|關鍵字:||water content;水分含量;temperature;drying-wetting;behaviors of potassium;溫度;乾溼交替;各型態鉀||出版社:||土壤環境科學系||摘要:||
在一般的田間狀態下，土壤的水分以及溫度境況並非恆定而為變動之情形，瞭解土壤水分與土壤溫度的變動對土壤中鉀的行為之影響，有助於研擬鉀肥之施用對策。本文之目的即在（1）探討土壤水分境況與乾溼效應對土壤鉀行為之影響；（2）探討土壤溫度境況對土壤鉀行為之影響；以及（3）探討土壤水分與土壤溫度境況之交互作用對土壤鉀行為之影響。本試驗取用強酸性之大肚山，以及石灰性之鹿港土壤，在添加鉀肥（150 mg / kg）及不添加鉀肥的情況下，設定下列三項實驗：（1）於25OC及不同水分含量（大肚山：-33kPa水分含量之100%及150%；鹿港：-33kPa水分含量60%，100%和150%）下，分別以溼土培育及乾溼交替培育三週；（2）於三種不同溫度（15 OC，25 OC，35 OC）下，進行溼土培育四週；（3）於溫度25 OC，35 OC與-33kPa水分含量60%和100%的組合處理下進行溼土培育三週。培育後測定各處理之溶液鉀，交換性鉀與非交換性鉀含量，並探討各型態鉀之消長情形。結果顯示，在三種水分含量下，大肚山土壤於-33kPa水分含量之150%時可釋出較多量之非交換性鉀，而鹿港土壤則發生鉀固定的現象。在乾溼交替之處理下，三次的風乾作用使大肚山土壤非交換性鉀之釋放減少，而對鹿港土壤而言，三次的風乾作用對其鉀固定能力並無太大的增減效應。在不同溫度處理下，大肚山和鹿港土壤隨溫度的上升，其非交換性鉀之釋放也提高，所以溫度的上升，對固定鉀之釋放有益。在不同水分含量與不同溫度之組合處理下，兩種土壤均在35℃及-33kPa水分含量的100%情況下，其易利用態鉀量（溶液鉀與交換性鉀的和）較高，換言之，在組合狀況將有助於增進土壤鉀之供應能力及鉀有效性。
Under general field conditions, the status of soil moisture and temperature regimes are variable. To investigate the changes of soil moisture and temperature which may affect the behaviors of potassium in soils will be helpful to build the suitable management of potassium fertilization. The purposes of this research were to study (1) the effects of soil moisture regime and drying and/or wetting on the behaviors of potassium; (2) the effect of soil temperature regime on the behaviors of potassium; and (3) the effects of the interactions of soil moisture and temperature regimes on the behaviors of potassium in the soils.A strongly acid soil(Da-Do Shan)and an calcareous soil(Lu Kuan)were sampled, followed by addition of K (150 mg K / kg) or none, and then incubated under three experiment conditions, including (1) incubated with different moisture conditions (Da-Do Shan: 100% and 150% of -33kPa water content; Lu Kuan: 60%, 100% and 150% of -33kPa water content) under drying-wetting and wetting cycles for three weeks at 25OC; (2) incubated with three temperature conditions (15OC, 25OC, 35OC) under wetting situation for four weeks at 100% of -33kPa water content; and (3) incubated with two temperatures(25OC and 35OC)and two moistures(60% and 100% of -33kPa water content)combinations under wetting situation for three weeks. After the incubations, the solution K, exchangeable K, and nonexchangeable K were measured, then the transformation of K forms in the soils of each treatment were investigated. Under different moisture conditions, Da-Do Shan soil released more nonexchangeable K, but Lu Kuan soil fixed more K at 150% of —33kPa water content. Under the drying-wetting incubations, three air-dry processes reduced the release of nonexchangeable K of Da-Do Shan soil; but for Lu Kuan soil, there was no significant effect on K fixation. Under different temperature conditions, the release abilities of nonexchangeable K were found to be increasing with soil temperature in two tested soils. It indicated that the process of increasing soil temperature will induce the release of fixed K. The results of the combination treatments of soil moisture and soil temperature showed that the treatment of 100% of —33kPa water content with 35OC had higher contents of readily available K, and lower content of nonexchangeable K. On the other hand, the K supply capacity and K availability in the soils were increased under such conditions.
|Appears in Collections:||土壤環境科學系|
Show full item record
TAIR Related Article
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.