By using the ratio of disaster-affected area,the ratio of disaster-suffering area,precipitation variability,fragile degrees,calamity loss rate,the temporal and spatial distributional characteristics of the agricultural risk of flood in Hunan province were evaluated.The results showed that the flood region had transferred from south to north in Hunan,and risk probability had a serious tendency.Based on temporal and spatial distribution characteristics of the agricultural risk degree of flood,some measures of disaster prevention and mitigation were proposed to provide a reference to avoiding or abating the influence of flood.

对湘阴县19 a(1986～2004)来稻瘟病发生的调查资料进行通径分析得出,雨日对早稻稻瘟病病害指数影响最大,其次为降水和日照,影响最小为温度.选用了温度(X1)、降水(X2)、日照(X3)、雨日(X4)4个气象因子与病害指数建立了湘阴县早稻稻瘟病预测预报模型y=-O.011 5-0.001 28 x1+0.002 74 x2-0.001 x3+O.019 724x4,预测的准确性达到显著水平.

对湘阴县19 a(1986~2004)来稻瘟病发生的调查资料进行通径分析得出,雨日对早稻稻瘟病病害指数影响最大,其次为降水和日照,影响最小为温度。选用了温度(X1)、降水(X2)、日照(X3)、雨日(X4)4个气象因子与病害指数建立了湘阴县早稻稻瘟病预测预报模型:y=-0.0115-0.00128x1+0.00274x2-0.0011x3+0.019724x4,预测的准确性达到显著水平。

通过播种期、密度、施肥方法等辅助试验,初步摸索出杂交稻以直播、适当稀植、一次性施肥为核心内容的高效栽培技术.不同栽培技术对比试验表明,高效栽培比SRI产量高0.9 t/hm2,增产10.14%,成本相当,利润高1 078.5元/hm2; 比双季稻常规栽培产量低1.78 t/hm2,低15.40%,但节省成本4 965元/hm2,利润高3 541.5元/hm2.投资效率高效栽培为104.3%,比SRI高21.9个百分点,比双季稻高85.2个百分点.