However, the capacities of the terrestrial and aquatic ecosystems required for their production are limited, while there are competing claims for their utilisation, and often not optimally managed, as shown for example by a severe decline in soil carbon content and fertility and fish stock depletion.
Tá cumas teoranta ag na héiceachórais trastíre agus uisceach atá riachtanach do tháirgeadh na n-acmhainní áfach, fad is a bhíonn éilimh ag coimhlint lena chéile maidir lena úsáid na gcumas sin, agus go minic ní dhéantar iad a bhainistiú ar an mbealach is fearr, mar atá léirithe mar shampla trí mheathlú mór a tháinig ar chion carbóin agus ar thorthúlacht na hithreach agus an t-ídiú ar an stoc éisc.