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根据关中地区麦红吸浆虫成灾的历史记载,及1948～2002年对吸浆虫在关中成灾的实际调查分析,结果表明,麦红吸浆虫灾害的空间格局特征是团块式,出现在局部地区,分布不均匀,团块大小不一,小到100～200m2,大到数公顷。麦红吸浆虫的灾害按照出现成灾田块的多少分为无灾( 级)、微灾( 级)、小灾( 级)、中灾( 级)和大灾( 级)5个等级,利用阶比法绘制陕西关中地区灾害阶比图,统计分析表明,陕西关中地区从1911～2002年的92年中,出现小灾( 级)以上灾害16年,占17.39%,成灾5次,相隔10年,19年,1年,32年;出现中大灾( 级与 级)10年,占10.87%,成灾4次,相隔1年,30年,1年;出现大灾( 级)7年,占7.60%,成灾3次,相隔1年,32年,均无明显的周期性。持续大灾2次,为1950～1952年和1985～1987年,均持续3年,相隔32年。是否具有30多年出现1次大灾的周期性,还需继续观察验证。每次大灾发生的地区不同,陕西关中地区20世纪50年代与80年代出现的2次连续3年大灾( 级),1950～1952年灾害最重的是关中中部的周至、户县、礼泉、兴平、武功,西部宝鸡地区(市)较轻,而1985～1987年严重灾害出现在西部的宝鸡地区(市)。
According to the historical record of the population of Midazolam in Guanzhong area and the actual investigation and analysis of the occurrence of Midazolam in Guanzhong from 1948 to 2002, the results showed that the spatial pattern of Midazolam was characterized by clumps, appearing in some areas and distribution Uneven, different sizes, as small as 100 ~ 200m2, a few hectares. According to the number of disastrous fields, the disasters of the imazapyr were divided into five levels of no disaster (grade), micro-disaster (grade), small disaster (disaster) Compared with the method of mapping the scale of disaster in Guanzhong area of Shaanxi Province, the statistical analysis shows that in the Guanzhong region of Shaanxi Province from 1911 to 2002, 92 catastrophes (grade) or above occurred for 16 years, accounting for 17.39% Years, 19 years, 1 year and 32 years; 10 years (10.87%) occurred in the disaster (level and level), 4 times in disaster, separated by 1 year, 30 years and 1 year; , Accounting for 7.60%, 3 times in disaster, separated by 1 year, 32 years, no obvious periodicity. Continued catastrophes twice, for the 1950 ~ 1952 and 1985 ~ 1987, all last 3 years, separated by 32 years. Whether there is more than 30 years there is a periodic disaster, the need to continue to observe and verify. Each disaster occurred in different regions, Shaanxi Guanzhong region in the 1950s and 1980s, two consecutive three-year cataclysm (grade), 1950 ~ 1952, the most serious disaster in central and central weeks, Huxian, ceremony Spring, Xingping, martial arts, western Baoji region (city) lighter, and 1985 ~ 1987 serious disaster in the western Baoji region (city).