Long - term changes in rain patterns linked to global warming and the paving over of habitat could be playing a role , said jessica hellmann , an entomologist with the university of notre dame who has examined shapiro ' s data 因此，最近的数周内，夏皮洛和他的学生在戴维斯地区只观测到了一只苎胥。而通常情况下，现在应该有很多苎胥出现才对。
2.
( 5 ) the hazard map is got by two kinds of methods of hazard assessment . after the analysis two kinds of assessment results both show that the most dangerous area in main urban area of wanzhou distributes the area along both sides of zhuxihe and the left side of yangtze river . this result agrees with the actual distribution of landslide , which proves that the assessment result is effective ( 5 )通过使用两种危险性评价方法，得到危险性图，对其分析发现两种评价的结果都显示，万州主城区危险性最高的区域主要分布在苎溪河两岸和长江的左岸，这与实际的滑坡分布基本吻合，这充分说明了评价结果的有效性。
