稻米為國人傳統主食，台灣傳統以移植稻方式在湛水狀態下栽培水稻，因此消耗較多的水資源，長期浸水的水稻田也導致田區甲烷生成的有利條件及改變植株養分的利用，若能改變水田水份管理方式，可以有效降低甲烷排放、改變植株養分利用狀態及維持產量。本論文於102年在嘉義鹿草地區及103年在台中霧峰地區，以節水栽培及慣行湛水栽培為水分處理，配合120 kg/ha、180 kg/ha、240 kg/ha的氮素處理，參試品種為台南11號及台稉9號，調查其在不同水分及氮素的處理組合下的生長情形、小區產量、氮素利用效率、水分生產力及甲烷排放量。兩地區四期作的試驗結果顯示，節水栽培依不同年期可節省約10-34%的灌溉水量，且能維持水稻在各產量構成要素的表現及一定的產量，氮素利用效率則會隨著氮素施用而下降。追蹤田區的甲烷釋放量，一期作主要在曬田前的營養生長期及穀粒充實期有明顯的甲烷排放量，二期作集中在曬田前的營養生長期，不同年期水田甲烷釋放的趨勢不一致，甲烷排放量因水分管理、氮肥處理；栽培生長期及監測取樣點不同有很大的差異。調查甲烷取樣點甲烷排放量與土壤環境因子的關係，顯示較高土壤溫度、較高土壤體積含水量、田區水位較高及較低土壤氧化還原電位有利於甲烷菌代謝而導致甲烷排放增加。Abstract
Rice (Oryza sativa L.) is the most important staples in Taiwan. Traditional transplanted rice with continuous standing water in Taiwan has relatively high water inputs. Flooding of the soil is a prerequisite for sustained emissions of methane and modifies nutrient use efficiencies. Manipulation of rice floodwater may offer a means of mitigating methane emission and changing plant nutritional status from rice fields without reducing rice yields. In this thesis, water-saving culture and flooding culture as water treatment and 120 kg/ha, 180 kg/ha, 240 kg/ha of nitrogen was applied at Lucao, Chiayi in 2013 and Wufeng, Taichung in 2014 respectively. Tainan 11 and Taikeng 9 was tested varieties to investigate the different treatment combinations of water and nitrogen applied on the rice growth conditions including plant height, yield components, yields, nitrogen use efficiency, water productivity and methane emission. The results showed that water-saving cultures depending on the cropping season can save about 10-34% of the irrigation water use, and can maintain the rice yield components in each performance and certain yields. Nitrogen use efficiency will decline as nitrogen over input. In 1st cropping season there were methane peak on the vegetative stage before midseason drainage and grain filling stage, while the peak appeared on the vegetative stage before midseason drainage in 2nd cropping season. Methane emission rates varied markedly with water regime, nitrogen treatment, cropping season, and monitor point. The relationship of soil character and methane emission rate at sampling sites revealed that higher soil temperature, increased in soil volumetric water content and lower soil redox potential were much appropriate for methanogenic bacteria and produced more methane emission in rice fields.中文摘要…………………………………………………………………I
英文摘要…………………………………………………………………II
目錄…………………………………………………………………………III
表目錄……………………………………………………………………IV
圖目錄……………………………………………………………………VI
前言…………………………………………………………………………1
前人研究………………………………………………………………4
材料與方法…………………………………………………………19
結果………………………………………………………………………26
一、不同試驗地區的土壤特性…………………………………………………………26
二、不同水分與氮肥處理下水分投入量………………………………………31
三、不同水分與氮肥處理下甲烷排放量………………………………………40
四、不同水分與氮肥處理下水稻性狀及產量構成要素……………62
五、不同水分與氮肥處理下氮肥利用效率與水分生產力………72
討論……………………………………………………………………………………………………………………80
參考文獻……………………………………………………………………………………………………………9
