水稻生產與農業環境之關係

The Relationship between Rice Production and the Agricultural Environment

姚銘輝(Ming-Hwi Yao) ； 朱鈞(Chun Chu)

《台灣農學會報》 16卷4期 (2015/12) Pp. 378-393

https://doi.org/10.6730/JAAT.201512_16(4).0006

摘要

農業生產面臨氣候變遷及極端氣象事件發生頻繁的威脅，衝擊全球糧食的供應，面對未來國際糧食短缺及糧價飆漲，維持臺灣糧食安全已列為國家安全層級的議題。過去對於農業的認知仍停留在產值不高，且使用大量土地及水資源，對環境造成負擔，糧食生產除攸關人類生存外，農作物耕作過程與環境的交感，仍有維持永續環境的積極面。水稻是臺灣主要糧食作物，自給率也達到90%以上，水稻田雖使用農業用水70%水量，但由土壤入滲以補充地下水，大量蒸發散調節氣候，當洪澇來襲，廣大稻田面積蓄積洪水，避免過多土壤沖蝕及減緩災害發生，這些都是水稻種植所衍生之環境效應。在溫室氣體排放的議題上，水稻田湛水土壤排放甲烷對環境造成威脅，但仍可透過適當水份管理方式減少排放量，另稻株可由葉片光合作用將大氣中二氧化碳氣體固定封存於土壤中，使農田由溫室氣體排放源轉為吸存源，皆有助於水稻生產在資源及環境永續利用之角色。

關鍵字

水稻 ； 逆境 ； 水資源 ； 溫室氣體 ； 碳封存

並列摘要

Agricultural production is facing frequent threats due to climate change and extreme weather events, which have serious impacts on the global food supply. The future prospects of global food shortages and increasing prices have become an issue at the national level for maintaining Taiwan's food security. In the past, the awareness of agricultural carried an image of large areas of land and substantial amounts of water that were consumed for a relatively low output. Even though food production is critical for human survival, this might impose a burden on agricultural processes and the environment. However, food production still maintains positive aspects of environmental sustainability. Rice is a main food crop in Taiwan, which can be over 90 percent self-sufficient even if 70 percent of the agricultural water was used. The water used for rice cultivation permeates into the soil to replenish the groundwater and leads to the regulation of climate by the substantial amounts of evaporation it permits. Most paddy fields can accumulate water when during flooding, so excessive soil erosion can be avoided and the losses from natural disasters reduced. These are some of the positive effects on the environment derived from the cultivation of rice. Another issue, however, concerns greenhouse gas emissions since the flooding of paddy fields may emit methane, which is detrimental to the environment. Butemissions can be reduced through appropriate water management, and the leaves of rice plants use photosynthesis that fixes carbon dioxide gas in the atmosphere to store it in the soil. This changes the greenhouse gas emissions from the paddy fields into a sequestration source, and thus contributes to the role of agriculture for the sustainable use of resources in the environment.

並列關鍵字

Rice ； Stress ； Water resource ； Greenhouse gases ； Carbon sequestration