Occurances of quarantine pests are very serious in every nursery of our city and have had a direct effect of the positive results of afforestation.

我市各苗圃检疫害虫的发生相当严重，已直接影响到造林绿化的成果。

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Among the different probablities of occurances and the social and economic losses of all kinds of natural disasters, flood and drought are the most frequent and serious.

在各种自然灾害的发生机率、对社会经济造成的损失中，又以水灾及旱灾最为频繁和严重。

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