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(1)这几年,喜鹊明显减少了,有人担忧再过些年孩子们可能连喜鹊也不认得了。(2)1993年春,笔者采用路线调查法,从宁夏的彭阳到银川400千米,在大约400平方千米的范围内只发现了50个喜鹊巢,至于喜鹊则更少见了,与20世纪70年代相比大约减少了95%。(3)原来群体数量很大的喜鹊为何急剧减少了呢?其一,因为喜鹊的栖息环境遭受破坏,可供营巢的大树太少了,致使90%的鹊巢只得筑在七八年生
(1) In recent years, the number of magpies has obviously decreased. Some people worry that children may not even know the magpies in a few years. (2) In the spring of 1993, the author used a route survey method to find 400 magpie nests within about 400 square kilometers from the Pengyang in Ningxia to Yinchuan, but the magpie was even rarer. In the spring of 1993, Approximately 95% reduction in the 1970s. (3) Why the number of large groups of magpies has drastically decreased? First, because of the destruction of the habitat of magpies, too few trees are available for nesting, leaving 90% of the magpies to be built only in 1988