Noun and の adjective
かそ
日本には、過疎に悩む地域がたくさんあります。
There are a lot of areas troubled with depopulation in Japan.
If the neglect of an area surpasses what was expected, then the result will be depopulation. No one wants to live in a neglected town, especially one that's worse than what they were told.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.