Tpo24阅读分析.doc

Tpo24 Reading 01 Lake Water (1) paragraph2: The questions e plicated when actual volumes of water are con sidered: how much water enters and leaves by each route? Discovering the inputs and outpu ts of rivers isa matter of measuring the discharges of every inflowing and outflowing stream and river. Then exchanges with the atmosphere are calculated by finding the difference bet ween the gains from rain, as measured (rather roughly) by rain gauges, and the losses by evaporation , measured with models that correct for the other sources of water loss. For the majority of lakes, certainly those surrounded by forests , input from overland flow is too small to have a noticeable effect. Changes in lake level not explained by river flows plus exchange s with the atmosphere must be due to difference between what seeps into the lake fr om the groundwater and what leaks into the groundwater. Note the word "net": measuring t he actual amounts of groundwater seepage into the lake and out of the lake isa much plicated matter than merely inferring their difference. 3. Which of the following can be inferred from paragraph 2 about the movement of water into a lake? ○ Heavy rain accounts for most of the water that enters into lakes. ○ Rainfall replaces approximately the amount of water lost through evaporation . ○ Overland flow into lakes is reduced by the presence of forests . ○ Seepage has a s