水作与地表覆盖旱作水稻的生长和水分利用效率

Growth and water use efficiency of rice cultivated under flood and non-flood soil with mulching

通过田间试验研究水作水稻和不同地表覆盖旱作水稻的生长和水分利用效率。结果表明 :水作稻田当季用水总量是旱作稻田的 3 5～ 3 7倍 ,旱作稻田灌溉水生产效率是水作稻田的 1 0 6～ 1 6 4倍 ,田间总水分利用效率也达到水作的 3倍左右。尽管地表覆盖有较好的保墒增温效果 ,但因水分胁迫使旱作水稻生育期较水作延长 4～ 1 0d ;旱作中的覆膜处理保墒增温效果最好 ,灌水量最低 ,其耕层土壤温度比其他旱作处理平均高 1℃ ,生育期延长时间最短。水作、覆膜、盖草和裸露处理的水稻产量分别为 95 74、 85 1 8、 84 81和 7833kg·hm-2 。覆膜处理虽在产量和水分利用效率上略高于盖草处理 ,但差异不显著 ,且覆膜处理存在成本高 ,污染土壤等缺陷。因此盖草不失为一项较好的替代水稻覆膜旱作的技术。

A field experiment was conducted to study the growth and water use efficiency of rice crop cultivated under flood and non flood soil mulched with different materials throughout the whole growing season.The total amount of water used by rice in flood soil was 3 53 7 times higher than that in non flood soil The irrigated water use efficiency by rice under flood condition was significantly different from the others( P <0 01)and the order of which was as follows:plastics film mulching,straw mulching,bare,flood.The whole growing period of rice crop cultivated under non flood condition was delayed for about 410 days in comparison with that under flood condition.The rice grain yields in the treatment of flood,plastics film mulch,crop straw mulch and without mulching were 9 574,8 518,8 482 and 7 833 kg·hm -2 ,respectively.There was no significant difference of rice grain yields between the treatments of straw mulching and plastic film covering but the cost and soil pollution in the latter should be concerned.It is suggested that rice crop could be grown well in non flood soil mulched with crop straw.