what exactly is changing pattern of land use?

Answer 1

Land space is used according to the way it is. If it is wet or dry, stable or runny, fertile or sandy. For farming for example you cannot always grow the same crops on the same field because the plants will eat out the land nutrients and it will become infertile. So what farmers do is establishing a pattern of what crops are grown because some plants eat a nutrient but leave another behind and some other plant feeds on that nutrient leaving another behind... that pattern keeps the land fertile for a longer time.