免耕稻-鸭生态种养技术的环境经济学分析

采用田间试验及环境经济学方法研究免耕稻-鸭生态种养技术的生态、经济效益。试验结果表明:农户采用免耕稻-鸭生态种养技术对稻田杂草的控制效果显著;在晚稻分蘖盛期和孕穗期,采用免耕稻-鸭生态种养技术对稻二化螟防效达100%,稻纵卷叶螟发生率分别比免耕抛秧不养鸭的稻田低48.05%、93.55%,免耕抛秧养鸭稻田中水稻纹枯病的病株率比免耕抛秧不养鸭的稻田分别低48.15%、38.21%;在稻田甲烷排放高峰期(晚稻分蘖始期-分蘖盛期),免耕抛秧养鸭对甲烷排放的控制效果明显,分别比翻耕抛秧不养鸭稻田、免耕抛秧不养鸭稻田的甲烷排放量减少4.723g/m2、2.333g/m2,晚稻整个生育期间,免耕抛秧养鸭稻田甲烷排放量比免耕抛秧不养鸭稻田减少3.37g/m2,比翻耕抛秧不养鸭稻田减少5.59g/m2;免耕可节约灌溉用水1300m3/hm2。环境经济学分析结果表明:采用免耕稻-鸭生态种养技术的农户比采用免耕抛秧不养鸭技术或采用翻耕抛秧不养鸭技术的农户分别增加财务净收益2166yuan/hm2、4207yuan/hm2;免耕抛秧养鸭获得的经济净效益为4062yuan/hm2,而免耕抛秧不养鸭、翻耕抛秧不养鸭的经济净效益分别为1592yuan/hm2、-997yuan/hm2。免耕稻-鸭生态种养技术既能充分发挥稻-鸭复合生态系统的生态和经济效益,又能较好地克服免耕给生态环境带来的不利影响,是一种很有发展潜力的可持续农业生产模式,具有良好的推广和发展前景。

An environmental economics analysis of a rice-duck ecological management technique with no-tillage

This study is aimed at the ecological and economical benefits of the rice-duck ecological management technique with no-tillage through the adoption of field experiment and environmental economic approaches. The results showed that the farmers' control over field weeds was remarkably effective with the application of this technique. In the initial tillering stage and the full tillering stage of late rice, the rice-duck ecological management technique with no-tillage was 100% effective in the prevention of Chilo suppressalis. The incidence rate of Cnephalocrocis medinalis was 48.05% and 93.55% lower, respectively, than that of the no-tillage cast-transplant area without duck. As for the diseased plant ratios of sheath blight in the no-tillage cast-transplant area with duck it showed 48.15% and 38.21% lower, respectively, than that of the no-tillage cast-transplant area without duck. The control of methane emission was apparently effective in the no-tillage cast-transplanted area with duck over the peak period (in the initial tillering stage and the full tillering stage of late rice), when compared with the conventional-tillage cast-transplant area without duck, showing a reduction of 4.723g/m~2. In comparison with the no-tillage cast-transplant area without duck, the amount of methane emission was reduced 2.333g/m~2. For the total course of late rice, the amount of methane emission in the no-tillage cast-transplant area with duck was reduced 3.37g/m~2 compared with that of the no-tillage cast-transplant area without duck, and reduced 5.59g/m~2 in comparison with that of the conventional-tillage cast-transplant area without duck. No-tillage could save 1300m~3/hm~2 of irrigation water. Analysis of environmental economics indicated: compared with the farmers who adopted the no-tillage cast-transplant without duck technique and those who adopted the conventional-tillage cast-transplant without duck technique,the farmers adopting the rice-duck ecological management technique with no-tillage showed a possible income increase of 2166yuan/hm~2 and 4207yuan/hm~2, respectively. The economic net benefit of the no-tillage cast-transplant with duck technique was 4062yuan/hm~2, and those using the no-tillage cast-transplant without duck technique and the conventional-tillage cast-transplant without duck technique respectively earned 1592yuan/hm~2 and -997yuan/hm~2. The rice-duck ecological management technique with no-tillage might not only bring about the ecological and economic benefits for a compound ecological system with rice-duck, but also may overcome the disadvantages that the no-tillage brings to the ecological environment, thus making it a sustainable agricultural production mode with a potential of promotion and development.