イオン交換樹脂および逆浸透膜を用いたコムギとオオムギの塩水灌漑栽培
スポンサーリンク
概要
- 論文の詳細を見る
塩水を農業用水として利用し淡水資源を節約するために，根域に除塩処理を施す塩水灌漑法を検討した．内径56㎜，長さ40㎝の塩ビ製のポットを用いた．ポットの底部には除塩効果があるアンバーライト（イオン交換樹脂）および逆浸透膜を設置する区と除塩効果がないラブシート（不織布）を設置する対照区を設けた．そしてポットに土壌を詰めコムギとオオムギを移植し，ポットの底から淡水および塩水で灌漑した．脱塩処理および灌漑に対する反応は２作物で同じであった．対照区では塩水灌漑によって生育が著しく抑制された．アンバーライト区で作物の生育は，淡水灌漑で対照区と変わらなかった．塩水灌漑ではアンバーライトによって乾物生産が対照区より向上したが，最終的な茎葉部と土壌のナトリウム含有率は対照区と変わらなかった．逆浸透膜は茎葉部と土壌のナトリウム濃度を低下させた．しかし逆浸透膜によって作物の生育は，淡水および塩水の二つの灌漑条件で対照区より著しく小さくなった．アンバーライトと逆浸透膜はともに除塩効果があった．しかし，アンバーライトは塩水処理能力の限界があること，逆浸透膜は水の移動が阻害されることが解決しなければならない課題であることが分かった．Saline irrigation equipped desaline apparatus in a root zone was tested to save fresh water resources. Pots of 56 mm inner-diameter and 40 cm in length were used. Amberlite (ion-exchange resin) and reverse osmosis membrane, both of which had a desalinating ability, were set at the bottom of each pot in desaline plots, respectively. In the control plot, a lovesheet (non-woven cloth) that had no ability to desaline was set. Wheat and barley were transplanted into these pots, which were filled with soil, and the pots were irrigated through the bottom either by fresh or saline water. The two crops responded to desaline methods and irrigation similarly. Growth and development in the two crops were suppressed largely by saline irrigation in the control plot. Amberlite did not affect the growth and development under fresh water irrigation. Shoot dry weight was increased by amberlite under saline irrigation, but the final values of sodium concentration of shoot and soil was not affected. The sodium concentration was reduced by reverse osmosis membrane, whereas the growth and development were suppressed under both fresh and saline irrigations. Amberlite and reverse osmosis membrane improved the growth and development and sodium concentration, but it should be a challenge to improve desaline ability of amberlite and water permeability of reverse osmosis membrane.
- 2010-02-01