长期使用利尿药的降压机理主要是：A．增加血浆肾素活性 B．排Na+利尿，降低血容量

Read the following text and choose the most suitable heading from the list A-F for each paragraph. There is one extra heading which you do not need.

A. The description of using amateur records to encourage the public. B. The description of old records kept by amateur naturalists. C. Concerns over amateur data for lacking objectivity and precision. D. The necessity of encouraging amateur collection. E. How people react to their involvement in data collection. F. The application of amateur records to phonology.

小题1:______________
Tim Sparks slides a small leather-bound notebook out of an envelope. The book’s yellowing pages contain beekeeping notes made between 1941 and 1969 by the late Walter Coates of Kilworth, Leicestershire. He adds it to his growing pile of local journals, birdwatchers’ lists and gardening diaries. "We’re uncovering about one major new record each month," he says, "I still get surprised." Around two centuries before Coates, Robert Marsham, a landowner from Norfolk in east of England, began recording the life cycles of plants and animals on his estate. Successive Marshams continued recording these notes for 211 years.
小题2:_______________
Today, such records are being put to uses that their authors couldn’t possibly have expected. These data sets, and others like them, are proving valuable to ecologists interested in the timing of biological events, or phonology. By combining the records with climate data, researchers can reveal how, for example, changes in temperature affect the arrival of spring, allowing ecologists to make improved predictions about the impact of climate change.
小题3:_______________
But not all professionals are happy to use amateur data. "A lot of scientists won’t touch them, they say they’re too full of problems," says Root. Because different observers can have different ideas of what forms, for example, an open snowdrop. "The biggest concern with ad hoc (临时的) observations is how carefully and systematically they were taken,” says Mark Schwarts of the University of Wisconsin, Milwaukee, who studies the interactions between plants and climate. "We need to know pretty precisely what a person’s been observing—if they just say ‘I noted when the leaves came out’, it might not be that useful.” Measuring the onset of autumn can be particularly problematic because deciding when leaves change color is a more subjective process than noting when they appear.
小题4:_______________
Overall, most phrenologists arc positive about the contribution that amateurs can make. "They get the raw power of science: careful observation of the natural world," says Sagarin. Others suggest that the right statistics can iron out some of the problems with amateur data. Together with colleagues at Wageoingen University in the Netherlands, environmental scientist Arnold van Vliet is developing statistical techniques to account for the uncertainty in amateur phonological data. Besides, the data are cheap to collect, and can provide breadth in space, time and range of species," It’s very difficult to collect data on a large geographical scale without enlisting an army of observers, says Root.
小题5:_______________
Phonology also helps to drive home messages about climate change. “Because the public understand these records, they accept them,” says Sparks. It can also illustrate potentially unpleasant consequences, he adds, such as the finding that more rat infestations are reported to local councils in warmer years. And getting people involved is great for public relations. "People are excited to think that the data they have been collecting as a hobby can be used for something scientific—it empowers them” says Root.