摘要
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)。
Based on the investigation and observation of the wheat midge,Sitodiplosis mosellana (Gehin),in Guanzhong,Shaanxi Province,and the analysis on the data recorded from 1911 to 2002,the spatial pattern of plague caused by the wheat midge is found to be masslike,occurring in part regions and distributing unevenly.The masses vary from a piece of wheat field or a concavity in it to several pieces of adjacent and homogeneous wheat field.The areas of a plague mass vary from 100 m2 to several hm2.According to the amount of outbreaking fields,the plague of the wheat midge can be classified into five grades:nonplague (grade Ⅰ),minute plague (grade Ⅱ),light plague (grade Ⅲ),moderate plague (Ⅳ),and heavy plague (grade Ⅴ).The degrees of its plague in Guanzhong were compared illustratively.The statistical analysis shows that during the 92 years from 1911 to 2002,there were 16 years occurring grade light,moderate and heavy plague (grade Ⅲ.Ⅳ.Ⅴ) (17.39%), being calamity 5 times apart 10,19,1,and 32 years respectively;10 years occurring moderate and heavy plagues (grade Ⅳ and Ⅴ) (10.87%),being calamity 4 times separated by 1,30,and 1 year respectively;7 years occurring heavy plague (grade Ⅴ) (7.60%),being calamity 3 times separated by 1 and 30 years and no apparent periodicity.The sustainable heavy plagues occurred twice in 1950 to 1952 and 1985 to 1987,all lasting for 3 years and separated by 32 years.Whether there occurs a heavy plague every 30 years or so needs to be further studied.The regions where each heavy plague occurred may not be the same.For example,the most serious calamity in 1950-1952 occurred in the central part of Guanzhong plain,including Zhouzhi,Huxian,Liquan,and Wugong counties;that in 1985-1987 occurred at the west part of Guanzhong,i.e.Baoji Prefecture (City).
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2003年第5期96-100,共5页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目(39770499)
