For example, land rented-in may previously have been used for other purposes whilst exporting is an additional work task to be accommodated.
Er enghraifft, mae’n bosibl y byddai tir a gaiff ei rentu wedi cael ei ddefnyddio at ddibenion eraill o’r blaen, ac mae allforio nitrogen yn dasg ychwanegol y mae angen darparu ar ei chyfer.