Dynamics of novel insecticide HNPC-A9908 residue in vegetable-field ecosystem

HNPC-A9908 （o-（3-phenoxybenzyl）-2-methylthio-1-（4-chlorophenyl） propyl ketone oxime）, a novel oxime insecticide, is a highly effective and broad-spectrum insecticide which can be widely used to control many species of foliar insects on various crops. A study was conducted to evaluate the fate of HNPC-A9908 and study the degradation dynamics of HNPC-A9908 residue in vegetable field ecosystem. The results showed that degradation of HNPC-A9908 was much faster in vegetable pakchoi than in soil, and its half-life in pakchoi and soil was 1.32 and 3.75 d, respectively. The final residue of HNPC-A9908 in pakchoi was at the undetectable level to 0.122 mg/kg. As a conclusion, a dosage of 90 g/hm^2 was suggested and considered to be safe to human beings and animals.

白鹤灌区农业干旱对气象干旱的响应关系

为了提高农业干旱预警能力和水平,以白鹤灌区为研究区域,利用气象干旱指标SPI(Standardized Precipitation Index)和农业干旱指标SSI(Standardized Storage Index),分析了白鹤灌区1990-2016年两种干旱在烈度和历时之间的响应关系,结果表明:①农业干旱的发生、历时、烈度除了与气象干旱的烈度、历时有关外,还与灌区作物用水过程具有关系。②1个月时间尺度的农业干旱的历时和烈度都对3个月的气象干旱的历时和烈度响应关系最好。③对比5种不同的响应关系,结合1个月时间尺度农业干旱对气象干旱的响应关系,1个月时间尺度的农业干旱对3个月的气象干旱的响应模型都以指数模型最好。干旱烈度和历时响应关系分别为:y=2.2115 e^(0.1017)x、y=2.7905 e^(0.0782)x。