论文部分内容阅读
苏北沿海垦区蛴螬混合种群发生影响因素有 :上年的越冬基数 (X1)、上年 12月至当年2月月均 2 0cm最低地温 (X2 )、6～ 8月份降雨强度 (X3)、秋熟经济作物种植面积 (X4 )和秋熟旱粮作物种植面积 (X5)。经逐步回归法优选出X2 、X3 和X4 建立了秋季蛴螬混合种群预报模型 ,经1974～ 1995年历史回报和 1996～ 1998年预报验证 ,效果良好 ,可以用于预报实践
The influential factors of the mixed population occurrence of 蛴 螬 in the northern coastal reclamation area are: the overwintering base (X1) in the previous year, the lowest average ground temperature (X2) of 20 cm in the previous year from December to February of the same year, the rainfall intensity (X3) from June to August, The area under cultivation of cash crops (X4) and the area under cultivation of dry farm crops (X5). Through the stepwise regression method, the mixed population forecasting model of autumn 蛴 螬 was established by X2, X3 and X4. The model was validated by the historical returns from 1974 to 1995 and the forecast from 1996 to 1998, and it can be used in forecasting practice