養液膜栽培（NFT）は、養液の薄い連続的な流れを、傾斜した水路の底に沿ってむき出しの植物の根の上に流す水耕栽培法です。上の根は酸素のために湿った空気中に残り、下の根は流れる膜から水とミネラルを吸収します。
主なポイント
- Shallow film of nutrient solution (2–3 mm deep) flows continuously through sloped channels
- Upper roots access atmospheric oxygen; lower roots absorb nutrients from the film
- Highly water-efficient — solution recirculates in a closed loop
- Best suited to fast-growing leafy crops and herbs
- Requires a reliable pump — power outages quickly stress roots
- Channel gradient of 1:30–1:40 (2–3 cm drop per metre) is critical for even flow