青海省气象干旱对粮食产量的影响及其评估方法研究

气象干旱是青海省发生最为频繁的气象灾害之一, 具有出现频率高、 持续时间长、 影响范围广等特点, 对农业生产造成极大的影响, 严重的干旱少雨之年常使农业大幅度减产, 甚至绝收. 为了研究气象干旱对青海省粮食产量产生的影响, 根据拉格朗日插值方法给出了青海省无干旱时"期望产量"的确定方法, 并据此求算出历年干旱对青海省粮食产量的损失量值, 然后依据农作物不同生育期所发生的干旱的强度、 范围以及作物对干旱的敏感度等关系, 建立了干旱损失量的统计和评估模式. 在2006-2010年青海省粮食产量评估中进行应用, 5 a中有4 a误差小于5%, 仅2006年误差百分率达到-9.38%; 由此, 证明了运用干旱损失评估方法, 可以评估出干旱对粮食产量的损失量, 从而评估出青海省的实际粮食产量, 效果较好, 可以在青海省今后的粮食产量预报和评估中推广应用.

The Impact of Drought on Grain Output in Qinghai Province and How to Assess

Climate drought is one of the most frequent meteorological disasters in Qinghai Province, which has high frequency, long duration, wide disaster range and great impact on agricultural production. Severe drought often makes agricultural production greatly reduced, or evens no production. In order to study the effect of climate drought on grain output in Qinghai Province, first, based on the Lagrange interpolation method, how to calculate the "expected yield" of no drought is determined, and then calculate the loss due to drought. Then according to the relationship with the drought intensity of the different growth stages, scope and crops sensitive to drought etc., statistics and evaluation model of drought loss might be set up. Applying the model in grain output assessment of Qinghai Province from 2006 to 2010, one can see that the error was less than 5% for four years, but was-9.38% in 2006. It is demonstrated that the assessment method can evaluate the drought loss of grain output, which could be used to assess the actual grain output of Qinghai Province with better effect. The method is suggested to forecast and assess the grain output in Qinghai Province from now on.