(1)比较两地区河流干流流向、流量变化的不同点,并做出合理解释。 _________________________________________________________________________________________ _________________________________________________________________________________________ (2)说明甲乙两河的航运效益差异,并简述差异产生的原因。 _________________________________________________________________________________________ _________________________________________________________________________________________ (3)据图分析,乙河流域内多洪涝灾害的主要自然原因是什么? _________________________________________________________________________________________ _________________________________________________________________________________________ |