碳酸氢铵撒干粉覆盖黑色塑料地膜灭钉螺效果观察

目的观察碳酸氢铵撒干粉覆盖黑色塑料地膜加不同用量,除和不除杂草的灭螺效果。方法选择1条有螺沟,分12段,试前进行钉螺基线调查。设碳酸氢铵覆盖除草5个组,剂量分别为100、200、300、400、500 g/m2;设碳酸氢铵覆盖不除草5个组,剂量同上;同时设不覆盖空白对照各1个组。试验后10、20、30、60、90、180 d按试前调查方法捕获土表钉螺观察,20 d时淘洗土内0～15 cm钉螺观察。结果不同剂量组氨浓度2 h达1 614～9 150mg/m3。空白对照除草和不除草10～180 d钉螺死亡率无增,活钉螺密度无下降;除草和不除草覆盖加碳酸氢铵100g/m2,10～180 d钉螺死亡92.55%～100%,螺密度下降90.61%～100%,土内钉螺死亡95.98%～96.74%;200 g/m2除草和不除草钉螺死亡95.92%～100%,密度下降93.27%～100%,土内钉螺死亡99.00%～99.6%;除草和不除草300、400、500 g/m2钉螺死亡和密度下降均100%,土内钉螺均死亡100%。结论黑色塑料地膜覆盖加碳酸氢铵一次性撒干粉100～500 g/m2对土表和土内钉螺均具有很好的杀灭效果,不除草与除草杀灭钉螺效果相近,加碳铵最佳用量300 g/m2,覆盖最佳时间10～20 d,省除草,省用水,省喷洒,省时省工,宜大面积推广应用。

The Molluscicidal Effect of Ammonium Bicarbonate Powdery Sprinkling by Earth Covered with Black Plastic Mulch

Objective The study was conducted to observe the molluscicidal effect of ammonium bicarbonate powdery sprinkling with different dosage as well as whether weeding is implemented.Methods Twelve sections of ditch were selected as pilot sites,in which 6 were weeded whileothers were not.Each section was powdery sprinkled with ammonium bicarbonate of different dosage(0,100,200,300,400,500 g/m2)and then the earth was covered with black plastic mulch.The molluscicidal effect was observed in 10,20,30,60,90,180 days after the experiment.Also needed is to observe the molluscicidal effect of snails in the surface layer of the soil in 20 days.Results No matter if weeding was taken place,the mortality and the reduce rates of density of snails remain unchanged.The mortality was 92.55-100% and the reduced rates of density of snails was 90.61-100% in10-180 days if the dosage of 100 g/m2.And with the dosage of 200 g/m2,the rate was 95.92-100% and 93.27-100%.Over 300 g/m2 the indices could be 100%.Ammonia concentration reached 1 614-9 150 mg/m3 in 2 hours.Conclusion The molluscicidal effect of ammonium bicarbonate powdery sprinkling by earth covered with black plastic mulch was perfect.Whether weeding is implemented did not mater.The best effect occurred when ammonium bicarbonate was perfect.Weeding or not did not mater.The best method was 300 g/m2 in 10-20 days without weeding.