Synthetic fertilizers are more heavily relied upon for crop production and manure use becomes a challenge as well as a source for pollution.
sɪnθˈɛɾɪk fˈɜːɾəlˌaɪzɚz ɑːɹ mˈoːɹ hˈɛvili ɹᵻlˈaɪd əpˌɑːn fɔːɹ kɹˈɑːp pɹədˈʌkʃən ænd mənjˈʊɹ jˈuːs bɪkˌʌmz ɐ tʃˈælɪndʒ æz wˈɛl æz ɐ sˈoːɹs fɔːɹ pəlˈuːʃən.