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应用生态经济学观点开展了雀麦防治指标的研究,将雀麦设置为5种密度,即0、7、14、21、28、35株/m~2。经田间小区试验,测定小麦产量损失率。田间试验表明,在单位面积上,随着雀麦数量的增加,小麦产量逐渐下降。通过4种曲线模拟及回归分析比较,得到雀麦密度与小麦产量损失率之间的关系为指数曲线,即y=0.928e~(0.0028/x)。根据Chiang的经济阈值计算模式,制定了在山西不同小麦产量水平和不同防治水平下的雀麦防治指标。即在防效90%,小麦单产500、400、300 kg/667m~2水平下,雀麦防治指标分别为3.26、4.08、5.45株/m~2;在防效80%,小麦单产500、400、300kg/667m~2水平下,雀麦防治指标分别为3.67、4.59、6.12株/m~2。
The application of ecological economics point of view to carry out the control index of broccoli, the set of five kinds of density, namely 0,7,14,21,28,35 plants / m ~ 2. After field plot test, determine the yield loss of wheat. Field experiments showed that on the unit area, with the increase of the number of broccoli, the wheat yield decreased gradually. By four kinds of curve simulation and regression analysis and comparison, the relationship between the density of the bird and the yield loss rate of wheat is exponential curve, that is, y = 0.928e ~ (0.0028 / x). According to the calculation model of Chiang’s economic threshold, the index of control of the firebrick was established under different wheat yield levels and different control levels in Shanxi. The results showed that under the control efficiency of 90% and 500,400,300 kg / 667m ~ 2 of wheat yield, the control index of the broccoli were 3.26,4.08,5.45 plants / m ~ 2 respectively. When the control effect was 80% and the yield of wheat was 500,400 , 300kg / 667m ~ 2 levels, the control index of 3.76,4.59,6.12 plants / m ~ 2 respectively.